Even before the final results are known, there are more than a few indicators of how the evening will go on caucus night. 
 
 Performance in key counties is revealing, and turnout, weather, and energy all play a role, too. As the evening progresses, there will also be signs of who has the endurance and support to go beyond Iowa once the voting is over — and who doesn’t. 
 
 Text Size - 
 
 + 
 
 reset Gearing up for caucus day Branstad: Iowa will winnow field 
 
 Below is POLITICO’s list of five things to watch on caucus night. 
 
 1) How high can Mitt go? 
 
 This is the most important question of the evening, after months of a primary season that has been, in one way or another, all about Mitt Romney. 
 
 The former Massachusetts governor is, by all accounts, within striking distance of a win in Iowa. His crowds have been big and, just as important, energetic. Romney has seemed relaxed and confident about his chances. 
 
 His backers have argued that he doesn’t need to win outright in order to be a winner, and that may prove true — but after closing-day polls showed him either winning or essentially tied for first place, anything lower than a close second will be tough to spin. 
 
 Further, if Romney can’t climb higher than the mid-20s — like Bob Dole in 1996 — it will keep alive the lingering questions about whether he can win over the leery Republican base. If he doesn’t get 28 percent, it will be a tough night for Romney, many insiders believe. 
 
 2) Turnout, turnout, turnout 
 
 Every election comes down to turnout and which side gets their supporters out. Tuesday night is no exception. 
 
 But not all ground games are equal. Romney and Ron Paul are the only two with the resources to turn out their supporters. Rick Santorum is running a shoestring operation based on momentum and, if he’s lucky, a late-breaking movement of the 2008 Mike Huckabee coalition in his direction — most notably social conservatives, evangelical voters, and home-schoolers. 
 
 If the weather is bad, the wide perception is that it will favor Paul, whose supporters are generally seen as more motivated than anyone else. The days leading up to the caucuses have been cold but dry (and manageable), meaning it’s possible that older voters could turn out. 
 
 Still, there has been a general enthusiasm gap among voters about a field that’s widely been panned as weak, and it remains to be seen if they’ll turn out in meaningful numbers. 
 
 A major question is whether Paul’s army has the depth to compete — and whether the results will be treated as legitimate. If entrance polling shows a high number of Democrats and independents showed up and switched registration at the door to caucus for Paul, some top GOP-ers — already fearful of what a Paul victory would do to the legacy of the Iowa caucuses — will use that as evidence to suggest it’s not a true win. 
 
 Another question is whether any of the mega-churches mobilize for Santorum. And aside from that, there is the matter of the broader role of evangelical voters — will they dominate or will the more secular question of electability, which is Romney’s calling card, end up ruling the day? 
 
 If turnout is high, it’s seen as favoring Romney. Lower turnout would benefit Paul and Santorum. 
 
 The turnout for the caucuses in 2008 was just under 120,000. Given the historic opportunity that Republicans see to beat President Barack Obama, anything less than that bar will add to the sense of restlessness that voters have about the field. ||||| Looking for news you can trust? 
 
 Subscribe to our free newsletters. 
 
 
 
 
 
 On Tuesday, after 13 debates, five different front-runners, and one unforgettable Gloria Allred press conference, the GOP presidential race will finally take its first, tentative steps toward clarity when upwards of 100,000 Iowans participate in the first-in-the-nation caucuses. A win on Tuesday isn’t exactly a ticket to the White House—no Republican caucus victor has gone on to win the presidency in the modern era—but a poor performance will almost certainly mark the end of the road for candidates like Rep. Michele Bachmann and former Sen. Rick Santorum. 
 
 Here’s how it works: As in any election, each voter is assigned to a precinct. A city like Waterloo would have multiple precincts; a flyspeck town in northwest Iowa might have just one (there are 1,774 in all). To participate, you show up at 7 p.m. and, after listening to speeches from fellow precinct members on behalf of their favored candidates, cast your ballot. Often, the speakers are respected community leaders whose words carry some weight; revered former Iowa State wrestling coach Jim Gibbons, for instance, told me he might speak on behalf of Santorum at his precinct. Democratic caucuses usually entail multiple ballots, but Republicans will vote just once. 
 
 So what should you watch for? Here’s a quick look at where the candidates stand, and how they’ve spent their final week before the big vote: 
 
 Rick Santorum‘s final pitch to Iowa voters on Monday centered, as you would expect, on social issues. In Polk City, a farming community north of Des Moines, he was joined by 13 of the 21 Duggars—stars of the TLC reality show 19 Kids and Counting, and celebrities among conservative home-schoolers. It was folks like the Duggars who pushed Mike Huckabee over the top in 2008. By the numbers: Number of Iowa counties visited, out of 99: 99; number of Pizza Ranch franchises visited: 33; number of sleeves on his sweater of choice: 0; number of members of his immediate family, out of 9, who do not belong to the National Rifle Association: 1; percentage of supporters who say they will definitely show up for their caucus: 76. 
 
 As my colleague Gavin Aronsen reports, Ron Paul’s path to victory depends heavily on an army of college activists who flew into the Hawkeye State for winter break. Over the last few weeks, GOP opponents have hit him hard for publishing a racist and anti-Semitic newsletter in the late ’80s and early ’90s, but he’s managed to climb toward the top of the polls and has saturated the airwaves with flashy ads touting his pro-life credentials and Chevy-truck-style consistency. By the numbers: Number of babies delivered, according to his campaign literature: ~4,000; number of volunteers his campaign paid to house at the YMCA camp in Boone: ~500; percent decrease in favorability ratings over the final week of the campaign, according to Public Polling Polling: 21. 
 
 After her triumph at the Ames Straw Poll in August, Michele Bachmann looked like a serious contender for the Republican nomination, but her campaign has since fallen apart. Bachmann’s top Iowa aide switched his support to Ron Paul late last week in a move that underscored just how dysfunctional her organization in the state was. She says she’s in the race for the long haul, but barring a miracle, she’s pretty much done. By the numbers: Percentage of Iowa Republicans who said they’d caucus for her on July 10: 25; percentage of Iowa Republicans who said the same on January 1: 7; salary paid to former top strategist Ed Rollins, who now says he never would have worked for her if had just Googled her: $90,000. 
 
 Rick Perry entered the race in August as a cocky, angry, anti-Obama candidate, but in the last week before the caucuses he’s resorted to taking shots—and cutting Jeopardy!-style radio ads—blasting Rick Santorum for helping secure funding for a teapot museum in North Carolina. He’s also more or less abandoned his original pitch as an economic miracle worker, and refocused his campaign around cracking down on gay and reproductive rights. Oh, and he still thinks gay sex should be illegal. By the numbers: Number of YouTube “dislikes” for his web ad, “Strong,” which lamented the end of Don’t Ask, Don’t Tell: 731,755; number of likes: 24,813; points fallen in the polls in Iowa since August 21: 41. 
 
 
 
 For a moment—a brief, eminently fascinating moment—Newt Gingrich looked like he might be the next Republican nominee. But after being swamped by negative ads from Ron Paul and a pro-Romney super-PAC, Gingrich has fallen back to earth hard. In Atlantic, Iowa, he was put on the defensive by his own supporters, who were concerned about his past support for global warming legislation, and his quasi-lobbying work for Freddie Mac (among other things). Gingrich is hoping outrage over a nonexistent EPA dust-regulation campaign will translate into support at the caucuses. By the numbers: Percentage points dropped from mid-December high-water mark: 20; number of days in between the launch of his campaign and the opening of a campaign office in Iowa: 183; date on which he told ABC’s Jake Tapper “I’m going to be the nominee”: January December 1. 
 
 And then there’s Mitt Romney, who stands to all but lock up the Republican nomination with a win tonight. He’d be in pretty good shape with a loss, too, provided he at least outperforms a couple of key rivals. After initially keeping his distance from Iowa, the former Massachusetts governor poured considerable resources into the state over the last month of the race and plans to spend Tuesday night in Des Moines—a sign he expects to do well. As one Romney aide told Politico’s Roger Simon, “Iowa is about eliminating Gingrich and Perry without us having to spend a lot of money to do so.” By the numbers: Number of different Republican rivals he has trailed in the polls in Iowa at some point or another: 5; amount, in millions, spent by his super-PAC on ads targeting Newt Gingrich: $3.5; number of staffers it takes to hold his chair in place; 1; number of chemicals it takes to hold his hair in place: 0; percentage of Iowa voters who said they’d vote for him on July 11: 18; percent who said they’d vote for him on January 1: 18. 
 
 How to watch: Check this space, and Twitter, for updates. Gavin Aronsen (@garonsen) and I (@timothypmurphy) will be reporting from Iowa all day. By 10 p.m., we should have some idea of how the night will turn out. ||||| Iowa became the stage for electrifying political theater on caucus eve as six GOP presidential candidates tried to make a last-minute connection with voters — all while hounded by hundreds of reporters who documented their every move in mini messages on Twitter. 
 
 An expected 115,000 to 120,000 Iowa Republicans will record their choices tonight, GOP strategist John Stineman of West Des Moines estimated. 
 
 The race has shaped up as a three-way dead heat among Mitt Romney, Ron Paul and Rick Santorum, according to The Des Moines Register’s Iowa Poll, conducted last week. But in a sign of how unsettled the race remains, 41 percent of those who have a first choice could still be persuaded to change their minds, the poll found. 
 
 After 354 days of campaigning and more than 900 events, from the sweaty heat of the Iowa State Fair to skin-biting wind on Monday, the candidates are making their final arguments. 
 
 They spent the final full day of campaigning before the first-in-the-nation vote in one last-gasp scramble, traveling from town to city. 
 
 The words “mob scene” cropped up on Twitter throughout the day Monday to describe campaign events, but it was all relative. 
 
 “Callista and I are overwhelmed by the turnout this week,” tweeted Newt Gingrich, who drew 125 in Independence, then 225 in Walford. 
 
 A tiny cafe in Polk City, with a 49-person capacity, was quickly jammed for Santorum. 
 
 “Our woman in IA, @ShushWalshe reports huge crowds at Santorum events. Like body-surfing huge. Get crushed in stampede huge,” ABC News’ @AmyEWalter tweeted. 
 
 About 200 people were there, inside and outside, with a heavy load of reporters. 
 
 At a supply warehouse in Dubuque, 600 people were treated to “Eye of the Tiger” and “Born Free” as they waited to see Romney. And before more than 600 in Marion, an upbeat Romney declared: “We’re going to win this thing.” (Aides said later he was referring to the nomination.) 
 
 The frenetic politicking will continue yet tonight. All 4,000 to 6,000 caucusgoers in Black Hawk County will gather under one roof — inside the UNI-Dome, Black Hawk County GOP Chairman Mac McDonald said. They will be divided into precincts to vote, with cameras from Fox News and CNN watching, he said. At least two candidates — Michele Bachmann and Gingrich — are expected to make personal pitches there about 6 p.m. 
 
 Here’s how the final day before the Iowa caucuses went down, per Twitter and Des Moines Register reporters on the scene: 
 
 MITT ROMNEY 
 
 On the road from Davenport (crowd of more than 300), one of Romney’s sons posted a Twitter photo of his father on the campaign bus. 
 
 “One of the vents on the bus is blowing cold air, so the mittster is duct taping it closed. Typical dad,” Tagg Romney tweeted. 
 
 Romney held rallies in four cities Monday, more campaigning than he’s done in Iowa on a single day since the 2008 cycle. The leader in the Iowa Poll is banking on his electability as a key to success. 
 
 Ron Breitbach, 51, of Dubuque, who caucused for Romney in 2008 and plans to do so again tonight, said: “He’s a problem-solver. He’s a leader.” 
 
 Breitbach, who owns a golf course and sports center, added: “He’s had so much success, and that’s what we need — we need someone with success for people to rally around.” 
 
 RON PAUL 
 
 Paul, who tweaks reporters for discounting him, descended into their lair Monday, the Marriott in downtown Des Moines. 
 
 “Ron Paul no fool,” tweeted @RogerPolitico. “Holding rally in hotel where 400 reporters are staying. I think all of them are here.” 
 
 Some of the bigfoots: Maggie Haberman of Politico, Joe Klein of Time, Soledad O’Brien of CNN, Dan Balz of the Washington Post, Carl Cameron of Fox News and Chris Matthews of MSNBC. 
 
 Hundreds of people packed the hotel meeting room. Paul also drew 200 in Cedar Falls and 300 in Cedar Rapids. 
 
 The TV camera crews beelined to the men in the Des Moines audience with heavy facial hair, tattoos and nose rings. 
 
 Aaron Lea, a 34-year-old painter from Des Moines with a grunge look, was pressed for interviews by three news agencies within minutes. 
 
 “You wouldn’t see people like this at a Bachmann or Mitt Romney rally, so it makes it a point of interest,” said Lea, an independent who will register as a Republican at the caucuses. 
 
 The Huffington Post’s @mlcalderone: “Sign at Paul’s Marriott event: ‘A Ron Paul win will discredit the mainstream media.’ ” 
 
 Paul, a libertarian-leaning Texas congressman in second place in the Iowa Poll, often starts out his speeches by attacking the sacred cow of military spending and predicts a looming global financial collapse. On Monday, he boiled down his message to one word: liberty. 
 
 RICK SANTORUM 
 
 Santorum, a Christian conservative from Pennsylvania, said at the Reising Sun Cafe in Polk City that he has raised more money in the last few days than he did in the last few months. 
 
 The Register’s latest Iowa Poll shows Santorum in third place, and rising. 
 
 Glenn Larson, a retired insurance underwriter from Clive, said Santorum represents his values: opposed to abortion, in favor of balancing the budget. 
 
 “I think he has been neglected and pushed aside by the liberal news media because they think he can beat Obama. They don’t want him to win,” Larson said. 
 
 Santorum knocked his rivals a bit. 
 
 “We aren’t looking for a chief executive officer. We’re looking for a commander in chief,” said @JimAcostaCNN, who caught the jab at Romney. 
 
 A bus with “Santorum for President” on the side appeared on the trail Monday. 
 
 “Chuck Laudner says when Rick Santorum saw the big bus festooned with his name … he said ‘I’m not paying for THAT!’ ” the Los Angeles Times’ @RAbcarian said. 
 
 The RV is just on loan, driven by the Duggar family of Arkansas, anti-abortion activists with 19 children. 
 
 Santorum drew more than 200 at the Pizza Ranch in Boone, including Fox News’ Bret Baier. Later, 400 people chanted “We pick Rick!” at an Altoona Pizza Ranch. 
 
 “Young woman just fainted at Santorum event it is so crowded,” reported the Register’s @WilliamPetroski from Boone. 
 
 NEWT GINGRICH 
 
 Gingrich, who last month declared certain victory in the nominating contest, talked again Monday about what he said was the unfair influence of negative ads in Iowa, and sounded a note of caucus defeat. 
 
 “Newt on IA: ‘I don’t think I’m going to win … I think the volume of negativity has done enough damage,’ ” @SarahH_CBSNJ tweeted as Gingrich talked to reporters in Independence. 
 
 Gingrich, a former U.S. House speaker, said: “It has nothing to do with governing America and solving our problems. It has everything to do with a very cheap and I think a very, very destructive model of politics, which is part of why Washington is sick today.” 
 
 At a later stop, he called the comment a mistake in wording, and pinned his hopes on the voters who say they could still change their minds. 
 
 Ed Larson and his wife, Janet, shook Gingrich’s hand, but they said they were not sure how they would caucus, since much of what happens depends on the consensus of their neighbors. 
 
 The Larsons downplayed Gingrich’s fourth-place ranking in the Iowa Poll. “It isn’t a concern because the polls are media-generated, and it changes every hour,” Ed Larson said. 
 
 RICK PERRY 
 
 “Perry press corp traveling 375 miles on the last day of the Iowa bus tour, ending the day with the stop we’ve all waited for — Perry, IA,” tweeted ABC News’ @ArletteSaenz. 
 
 When the Texas governor was introduced in Sioux City as the “next governor of the United States,” the crowd laughed. That got tweets with #oops hashtags. 
 
 Perry, who is fifth in the Iowa Poll, made a final plea to the crowd of 100: Decide by conscience, not poll numbers. 
 
 “A voter asks Perry what she can do to make him seem more electable in next 30 hours,” the Register’s @JoshHafner tweeted. “Perry says #iacaucus is just ‘mile one’ in a marathon.” 
 
 Perry said his campaign has the organizational endurance to win the nomination. 
 
 Jan Hansen, a teacher from Le Mars, decided in Sioux City that she’s caucusing for him. “I hear people saying all the time we need to choose the candidate that we feel is the most electable,” she said. “Vote your heart. That’s what he said.” 
 
 MICHELE BACHMANN 
 
 “Vote for a strong Iowa woman!” Bachmann told one backer amid a crush of people at Paula’s, a small restaurant in West Des Moines’ Valley Junction. 
 
 “You got a camera? We should take a picture. And then go home and Facebook it. Tell everybody to come out and caucus,” the Minnesota congresswoman said. 
 
 The crowd was in the dozens rather than hundreds. A team of 22 juniors and seniors from Blake School in Minneapolis was on a school-sponsored trip to witness the caucuses. 
 
 “Mostly Obama fans. No love for hometown Bachmann,” messaged the Register’s @JasonNoble1. 
 
 Bachmann, who had a horde of reporters turn up (Tucker Carlson, Andrea Mitchell and David Brooks),wandered to the Diggity Dog puppy treat shop, where her husband, Marcus, bought gifts for the family dog, Boomer. 
 
 Bachmann was up at dawn for TV appearances on “The Early Show” on CBS and “Morning Joe” on MSNBC. She ended her day with a 9 p.m. rally at campaign headquarters in Urbandale. 
 
 Standing on a pickup truck tailgate, Bachmann thanked perhaps 150 volunteers for their work on her behalf. 
 
 Des Moines voter Sally Mead said after hearing Bachmann in West Des Moines: “I’ll follow with whatever she has in mind that she thinks is right. She’s genuine.” ||||| There are 99 counties in Iowa, but they’re not all equal in politics. Some matter more because of their sheer size. Others have a special relevance rooted in their history as bellwethers. Either way, those standout counties provide a revealing snapshot of what’s happening in the first presidential nominating contest. 
 
 Here are 10 counties to follow on caucus night to get a feel for who’s doing well in the caucuses and who’s not. 
 
 Text Size - 
 
 + 
 
 reset 
 
 Black Hawk County 
 
 With the University of Northern Iowa and a strong organized labor presence, Black Hawk County is reliably Democratic. But Waterloo is the city where Michele Bachmann was born — and it might also be said to be the place where her campaign went off the rails after Rick Perry outshined her at the county GOP dinner there the day after the Ames Straw Poll. In 2008, it was Mike Huckabee territory, with the Arkansas governor winning 35 percent to Romney’s 27 percent. 
 
 Dallas County 
 
 A suburb of Des Moines, Dallas County is Iowa’s fastest-growing county. Mitt Romney and Huckabee battled to a near-tie here in 2008 — just 4 votes separated the two candidates, with Romney squeaking to victory. That made Dallas County something of an anomaly, since it was the only county in the Des Moines metro area to vote for Romney over Huckabee. Caucus turnout tends to be very high here; in 2008, it posted one of the highest turnout levels in the state at 30 percent. 
 
 Dubuque County 
 
 This was Romney country in 2008, a place where he ran strong (41 percent) and Huckabee ran poorly (15 percent) — it was the only county in the state where the Arkansas governor failed to finish either first or second. But northeastern Iowa is the most heavily Roman Catholic part of the state, and the city of Dubuque is also home to a large concentration of Catholics who might find the candidacies of Rick Santorum and converted Catholic Newt Gingrich appealing. Still, if Romney’s not winning here, he’s probably in trouble. 
 
 Johnson County 
 
 Even this liberal enclave, home to Iowa City and the University of Iowa, matters to the outcome Tuesday evening: It’s still home to more Republicans that most counties in Iowa. Four years ago, it handed Romney a 360-vote victory, and there’s no reason he can’t carry it again. But keep an eye on Ron Paul — his anti-war and anti-establishment views are popular with college students and he ran 5 percentage points higher than his statewide average here in 2008. 
 
 Linn County 
 
 Home to Cedar Rapids, the second-largest city in Iowa after Des Moines, Linn County counts healthy contingents of both moderates and social conservatives. Like much of eastern Iowa, this was Romney turf in 2008: He captured 31 percent here, 6 percentage points above his statewide average, while Huckabee won 26 percent, 8 points below his statewide performance.
– Tonight’s the night! At 7pm CT, Iowa Republicans will gather to cast the first votes in the Republican nominating season. Consider this your pregame report, with info from Politico, Mother Jones, and the Des Moines Register: The frontrunners: Polls show Ron Paul, Mitt Romney, and Rick Santorum are poised to grab the proverbial “three tickets out of Iowa.” Romney doesn’t need to win to remain the favorite for the nomination, but anything less than a respectable second will be damaging. Turnout is everything: If it’s high, that’s probably a good sign for Romney. If it’s low, it’s a good sign for Paul and/or Santorum—depending on where it’s concentrated. Bad weather is thought to favor Paul’s band of enthusiastic supporters. Location, location, location: Romney’s support is strongest in eastern Iowa, Santorum should fare well in the northwest, and Paul is hoping for turnout in college towns such as Ames. Politico highlights 10 counties to watch here. The battle for fourth: If either Newt Gingrich or Rick Perry can pull out a closer-than-expected fourth, they might be able to stay in the race. Last-minute campaigning: Romney held rallies in four cities yesterday, his most since 2008. Paul held forth in a hotel full of journalists in Des Moines, hoping to grab media buzz. And Santorum appeared with the cast of 19 Kids and Counting, the TLC reality show beloved by Iowa homeschoolers. Some intriguing numbers: Paul’s favorability has fallen 21 points in the past week. Only 76% of Santorum’s supporters say they’ll definitely caucus for him. Romney, meanwhile, has at some point trailed five different candidates in Iowa—and is now polling at exactly the same 18% he was at in January.