-LRB- CNN -RRB- -- Sen. John McCain played offense against Sen. Barack Obama during much of the final presidential debate as he challenged his rival on his policies , judgment and character . Obama said he is the candidate who can bring `` fundamental change '' to the country and continued to try to link McCain to President Bush . In one of the more forceful moments of the debate , McCain turned to Obama and said , `` I am not President Bush . '' `` If you want to run against President Bush , you should have run four years ago . I 'm going to give a new direction to this economy and this country , '' the Arizona senator said . Watch McCain say he 's no Bush '' McCain aides said they had been working on him to be more explicit in drawing a distinction between himself and Bush . With less than three weeks before the election , it was one of several jabs McCain took at his opponent , who is leading the race in most national polls and has an 8-point lead in CNN 's average of national polls . A CNN/Opinion Research poll of people who watched the debate found 58 percent said Obama did the best job while 31 percent said McCain did . Watch entire debate : Part 1 '' | Part 2 '' | Part 3 '' The poll has a margin of error of plus or minus 4 percentage points , and the sample of debate-watchers in the poll were 40 percent Democratic and 30 percent Republican . McCain touted what he called his `` long record of reform '' and said to Obama : `` You have to tell me one time when you have stood up with the leaders of your party on one single major issue . '' Obama said he has a `` history of reaching across the aisle '' and pointed to his support for charter schools , pay for performance for teachers and clean coal technology . See scenes from the debate '' `` Sen. Obama , your argument for standing up to the leadership of your party is n't very convincing , '' McCain said . The third and final presidential debate took place at Hofstra University in Hempstead , New York , and was moderated by Bob Schieffer of CBS News . Analysts weigh in on the debate '' As McCain tried to put the pressure on Obama , he told the Illinois senator that voters need to `` know the full extent '' of his relationship with Bill Ayers , a former 1960s radical who belonged to the Weather Underground . `` Mr. Ayers is not involved in this campaign , he has never been involved in my campaign , and he will not advise me in the White House , '' Obama said . McCain 's campaign has charged that Obama 's association with Ayers should cause voters to question his judgment . Ayers was a founding member of the radical Weather Underground , a group that was involved in bombings in the early 1970s , including attacks on the Pentagon and the Capitol . Obama said Ayers had committed `` despicable acts '' 40 years ago , but pointed out that he himself had been 8 years old at the time . Watch what Obama says about Ayers '' Obama said Ayers has become the `` centerpiece '' of McCain 's campaign and said the fact that McCain keeps bringing Ayers up `` says more about your campaign than it says about me . '' The Republican nominee also brought up comments made last weekend by Rep. John Lewis and pushed Obama to repudiate them . Lewis on Saturday compared the feeling at recent GOP rallies to those of segregationist George Wallace . `` I think Congressman Lewis ' point was that we have to be careful about how we deal with our supporters , '' Obama said . `` I do think that he inappropriately drew a comparison between what was happening there and what had happened during the civil rights movement , and we immediately put out a statement saying that we do n't think that comparison is appropriate , '' he said . As the candidates butted heads over tax policy , both made frequent mention of `` Joe the plumber . '' Watch voters react when ` Joe ' comes up '' Last weekend , while Obama was canvassing for support in Holland , Ohio , the Democratic nominee ran into a man since dubbed Joe the plumber . In that exchange `` Joe '' asked Obama if he believed in the American Dream -- he said he was about to buy a company that makes more than $ 250,000 a year and was concerned that Obama would tax him more because of it . Obama explained his tax plan in depth , saying it 's better to lower taxes for Americans who make less money , so that they could afford to buy from his business . At the debate Wednesday , McCain characterized Obama 's plan as trying to `` spread the wealth around . '' Watch the candidates debate tax plans '' `` We 're going to take Joe 's money , give it to Sen. Obama , and let him spread the wealth around . I want Joe the plumber to spread the wealth around , '' McCain said . He added , `` Why would you want to increase anybody 's taxes right now ? Why would you want to do that to anyone , anyone in America , when we have such a tough time ? '' Obama countered that both he and McCain want to cut taxes , but that his plan would cut taxes for `` 95 percent of American families , '' more than McCain 's plan . On spending , Obama promised as president he would `` go through the federal budget page by page , line by line , and cut programs that do n't work , '' echoing a vow his rival has made repeatedly . McCain in turn promised an `` across the board spending freeze . '' He said he would balance the federal budget in four years , and went on to name specific programs including subsidies for ethanol when Schieffer pressed both candidates to identify specific budget cuts they would make . The candidates also talked about abortion rights , a topic not addressed in the previous presidential debate . Watch the candidates debate abortion '' McCain refused to commit to nominating only judges who opposed abortion , saying he would `` never impose a litmus test '' on court nominees . But he qualified the statement a moment later , saying he would base his nominations on `` qualifications '' -- and that he did not believe a judge who supported Roe v. Wade , the case that legalized abortion , `` would be part of those qualifications . '' McCain hammered Obama on abortion , accusing him of `` aligning himself with the extreme aspect of the pro-abortion movement in America . '' Obama rejected the charge out of hand , saying : `` Nobody is pro-abortion . '' He advocated sex education as a way of reducing the number of unintended pregnancies that result in abortions . `` We should try to prevent unintended pregnancies by providing appropriate education to our youth , communicating that sexuality is sacred and they should not be engaged in cavalier activity , '' he said . At the conclusion of the debate , Schieffer signed off with a line borrowed from his mother : `` Go vote now . It will make you feel big and strong . ''