Boston , Massachusetts -LRB- CNN -RRB- -- In a stunning upset that reshaped the U.S. political landscape , Republican Scott Brown won Tuesday 's special election in Massachusetts for the U.S. Senate seat formerly held by liberal Democrat Ted Kennedy . Brown defeated Democrat Martha Coakley , the state attorney general . Brown 's victory made real the once unthinkable prospect of a Republican filling the seat held by Kennedy , known as the liberal lion , for almost 47 years until his death due to brain cancer last August . Before Kennedy won the seat for the first time in 1962 , his older brother John held it for nearly eight years until his election as U.S. president in 1960 . `` This really does change everything , you know that ? '' said Mitt Romney , the former GOP governor of Massachusetts who introduced Brown at his victory rally . Share your thoughts on the election results Voters across Massachusetts braved winter cold and snow for an election with high stakes -- the domestic agenda of President Obama , including his top domestic priority , health care reform . Brown 's victory strips Democrats of their 60-seat Senate super-majority , needed to overcome GOP filibusters against future Senate action on a broad range of White House priorities . Senate Democrats needed all 60 votes in their caucus to pass the health care bill , and the loss of one seat now imperils generating that support again for a compromise measure worked out with the House . `` Forty one , forty one , '' chanted the crowd at Brown 's rally , referring to his new status as the Senate 's 41st Republican . Brown , a state senator until now , heralded his victory as the start of more election surprises in 2010 . No Republican had won a U.S. Senate race in Massachusetts since 1972 , and Democrats control the governorship , both houses of the state legislature , and the state 's entire congressional delegation . `` When there 's trouble in Massachusetts , rest assured there 's trouble everywhere , and they know it , '' Brown said of the Democratic Party . Republican leaders sounded a similar theme , saying Americans were fed up with what they called Democratic arrogance in Washington . `` Americans are investing their hopes in good Republican candidates to reverse a year-long Democrat trend of ignoring the American people on the issues of health care , spending and the growth of government , '' Senate Minority Leader Mitch McConnell , R-Kentucky , said in a statement . The seat vacated by Kennedy 's death is currently held by his former aide and longtime friend Paul Kirk , who was appointed on an interim basis . Obama called Brown and Coakley on Tuesday night , and a White House statement said the president `` told Sen. Brown that he looks forward to working with him on the urgent economic challenges facing Massachusetts families and struggling families across our nation . '' Massachusetts Secretary of State Bill Galvin said last week that certifying Tuesday 's election results could take more than two weeks -- potentially enough time to allow congressional Democrats to pass a final health care bill before Brown is seated . But multiple Democratic sources said that is unlikely . Even if House and Senate Democrats could reach a deal to meld their bills and pass them in the next couple of weeks , there would be a huge outcry from not only Republicans , but also an increasingly distrustful public if they appeared to be rushing it through . Galvin had predicted as many 2.2 million of the state 's 4.5 million registered voters would vote -- at least double the turnout from December 's primary . In one sign of high interest , more than 100,000 absentee ballots were requested ahead of the election , according to Brian McNiff , Galvin 's spokesman . Coakley was initially expected to easily win the race to replace Kennedy , who made health care reform the centerpiece of his Senate career . Until recently , Brown was underfunded and unknown statewide . Waging a nationally backed campaign that included driving his pickup around the state , Brown surged in the weeks preceding Tuesday 's vote and led in all the final polls . In a sign of the high stakes involved , the Coakley campaign held an afternoon news conference Tuesday to complain that voters in three places received ballots already marked for Brown . McNiff confirmed that the secretary of state 's offices received two reports of voters saying they received pre-marked ballots . The suspect ballots were invalidated and the voters received new ballots , McNiff said . Kevin Conroy , the Coakley campaign manager , said the `` disturbing incidents '' raised questions about the integrity of the election . In response , the Brown campaign issued a statement criticizing Coakley 's team . `` Reports that the Coakley campaign is making reckless accusations regarding the integrity of today 's election is a reminder that they are a desperate campaign , '' Daniel B. Winslow , the counsel for the Brown campaign , said in the statement . Obama had been `` surprised and frustrated '' by the race , White House Press Secretary Robert Gibbs said Tuesday . Obama and former President Bill Clinton hit the campaign trail in the final week in an attempt to save Coakley 's campaign , which observers say was hampered by complacency and missteps . Obama crushed Sen. John McCain in Massachusetts in 2008 , beating the GOP presidential nominee by 26 points . `` If you were fired up in the last election , I need you more fired up in this election , '' Obama urged a crowd at a Coakley campaign rally on Sunday . Vicki Kennedy , the late senator 's widow , called on state Democrats to turn out to save her husband 's legacy . `` We need your help . We need your support . We need you to get out there and vote on Tuesday , '' Kennedy said . `` We need you to bring your neighbors . We need you to bring your friends . '' Brown , who has trumpeted his 30 years of service in the National Guard , hewed to traditional GOP themes in his victory speech . He promised to back tax cuts and be tough on terrorists , and to oppose Obama 's health care overhaul effort . `` People do not want a trillion dollar health-care plan that is being forced on the American people , '' Brown said . Brown said his victory defied `` the odds and experts '' who predicted that the Senate seat held by Democrats for more than 50 years would not change hands . Instead , independent voters who outnumber registered Democrats and Republicans combined in Massachusetts strongly supported Brown . `` Tonight , the independent majority has delivered a great victory , '' Brown said , later adding : `` What happened here in Massachusetts can happen all over America . '' Facing the possibility of Coakley 's defeat , Democrats were trying to figure out whether they could pass a health care overhaul without that crucial 60th Senate vote . But top White House aides publicly insisted they were not engaging in any talk of contingency plans because they thought Coakley would win . Two Democratic sources in close contact with the White House told CNN on Monday that they 'd urged the administration , in the event of a Brown victory , to push House Democrats to pass the Senate 's health care bill as currently written . Doing so would prevent the plan from having to be taken up by the Senate again . `` I think the Senate bill clearly is better than nothing , '' House Majority Leader Steny Hoyer , D-Maryland , said Tuesday . A third option would be for Democrats to revisit the idea of trying to push health care through the Senate with only 51 votes -- a simple majority . But to do that Democrats would have to use a process known as reconciliation , which presents technical and procedural issues that would delay the process for a long time . A number of Democrats are eager to put the health care debate behind them and move on to economic issues such as job creation as soon as possible this election year . Senate Democrats could also try again to get moderate GOP Sen. Olympia Snowe of Maine to vote for a compromise health reform plan . Multiple Democratic sources , however , have said they think that is unlikely now . CNN 's Jim Acosta , Dana Bash , Kevin Bohn , Ed Henry , John King , Suzanne Malveaux , Shawna Shepherd , Jessica Yellin , Kevin Bohn , Alan Silverleib and Tom Cohen contributed to this report .