(CBSNews.com) - It's all over but the voting.
Following an exhausting home stretch sprint through the battleground states, President Obama and Mitt Romney will be mostly on the sidelines Tuesday as millions of Americans head to the polls. Romney has scheduled stops in Cleveland and Pittsburgh to thank volunteers and encourage supporters to vote, but there will be no more campaign rallies for either candidate. The 2012 presidential campaign - the most expensive in history, at nearly $2 billion - is finally coming to an end.
The president spent Monday trying to shore up his Midwestern firewall, making stops in Ohio, Wisconsin and Iowa - and appearing alongside supporters Bruce Springsteen and Jay-Z. Entering Election Day, most polls suggested the president had narrow leads in all three states, though Romney was within striking distance. If the president triumphs in the states he visited Monday - along with the states he is expected to win - he will have in excess of the 270 electoral votes he needs for another four years in office.
At an appearance in Madison, Wis., the president once again deemed Romney a "talented salesman" who is seeking "to repackage the same old bad ideas and make them out to be good ideas." He also attacked his rival for trying to appropriate the mantle of change that Mr. Obama rode to victory four years ago.
"[W]hen I say, Wisconsin, that I know what real change looks like, you've got cause to believe me because you've seen me fight for it, you've seen me deliver it, you've seen the scars on me to prove it, you've seen the gray hairs on my head to show you what it means to fight for change," said Mr. Obama.
Romney spent Monday in four states: Florida, Virginia, Ohio and New Hampshire. In Florida, he told supporters that the nation is "one day away from the first day of a new beginning." He argued that Mr. Obama does not deserve to be reelected because he has failed to reach across the aisle.
"If he can't work with Congress, think what happens the next time the debt ceiling comes up," Romney said. "All right, there will be threats of shutdown and default. And what that means is the economy freezes and jobs aren't created."
Though the candidates are dead even in national polls, the battleground state polls suggest Mr. Obama enters Election Day with an edge. In addition to the three states he visited Monday, he appears to hold a clear lead in Nevada and a small advantage in New Hampshire. Romney's only clear lead is in North Carolina, though surveys out of Florida suggest he may hold a slight advantage there as well. (The remaining battlegrounds, Virginia and Colorado, look just about dead even.) While there are 237 electoral votes that are almost certain to go to Mr. Obama, there are just 191 that are almost certainly in Romney's column. That means that even if he wins Florida's 29 electoral votes, Virginia's 13 electoral votes and Ohio and North Carolina's 15 electoral votes each, Romney would still need another battleground state to reach the 270 electoral vote threshold necessary for victory.
In an effort to expand the electoral map, Romney has made a late run at Pennsylvania, where recent polls have shown him within striking distance of the president. If Romney can secure 20 electoral votes from the Keystone State, which Mr. Obama won by ten percentage points four years ago, it would dramatically expand his potential paths to victory.
David Axelrod, senior adviser for the Obama campaign, told CBS News Monday that while he expects the race to be close, "we have a good chance to break 300" electoral votes. Despite a narrower path to victory, the Romney camp is also exuding confidence: It has pointed to polls suggesting greater voter enthusiasm among Republicans to argue that a robust turnout among Romney supporters will allow the former Massachusetts governor to cruise to a clear victory.
Romney votes in Belmont, Mass., on Tuesday morning before his trip to Ohio and Pennsylvania; he will return to Massachusetts to watch the returns with staffers and supporters in Boston. Mr. Obama, whovoted early in an effort to encourage supporters to do the same, will watch the returns from his campaign headquarters in Chicago.
Even before Election Day got underway, problems were emerging for some Americans seeking to cast their ballots. In New York and New Jersey, election officials were scrambling to accommodate voters in the wake of Superstorm Sandy; New Jersey voters were given the option to vote by email or fax, while in New York officials are allowing voters to cast ballots at any polling place. In Miami on Sunday, election officials temporarily closed their doors to voters who stood in long lines in an effort to cast early absentee ballots amid a bitter fight between the state Democratic and Republican parties over early voting. In Ohio - where a tight result could mean weeks of battles over provisional and absentee ballots and other issues - Republican Secretary of State Jon Husted is facing judges over a directive that could mean the invalidation of certain provisional ballots.
The presidential race is not the only contest taking place Tuesday, of course. Americans will also cast ballots in Senate, House and gubernatorial races and decide ballot measures on issues including taxes, same-sex marriage, the health care law and the legalization of marijuana. Republicans are expected to maintain control of the House, though Democrats could make gains; Democrats are expected to maintain their advantage in the Senate, though there are enough close races that Republicans are holding out hope for a takeover.
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