MORRISVILLE, Pa. -- Republican Mitt Romney has less than 36 hours leftto make his case to voters as to why they should fire President Obamaas national polls continue to show the race as a dead heat.

ASunday evening trip to Pennsylvania, the first time the campaign hasstopped there in weeks, was part of a last-minute push to win the statethat hasn't voted for a Republican since 1988.

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"This audience andyour voices are being heard all over the nation," Romney said to sea ofpeople who waited several hours to hear him speak. "They're being heardin my heart. The people of America understand we're taking back theWhite House, because we're going to win Pennsylvania," he said.

Romneyadviser Kevin Madden said the last 48 hours of the campaign was "theperfect time" to go to the state where they do not have the option tovote early.

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"We've seen that state just get closer and closer andcloser. ... We're essentially tied," he said. "We're overperforming inmany of these critical areas of the state, like the Philadelphiasuburbs, areas like Scranton, southwest Pennsylvania."

A Tribune-Review/Susquehanna poll released Saturday showed Romney and Obama tied 47%-47%.

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Theevent began more than an hour late after a travel delay in Cleveland,causing those at the rally to have to wait several hours to see Romneyafter the sun had gone down. This led to a commotion near the press areawhen a small group of people tried to leave the rally though a secureperimeter established by the Secret Service. Some of the attendeescomplained that they were cold and felt trapped; with the aid of Romneyadvance staff and the Secret Service, they were redirected to usableexits.

Throughout the weekend, Romney stopped in eightbattleground states where he touted his ability to reach across theaisle and pledged to work closely with Democrats if he is elected.Crowds ranging from 2,000 to more than 17,000 crowded into airplanehangars, amphitheaters, factories and warehouses to hear Romney'smessage of "real change."

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"Now on Tuesday, the choice of theAmerican people could lead to one of two very different destinations,"Romney told a rally in Cleveland. "If the president were to bere-elected he would, it's possible but not likely, if he were to bere-elected, he will still be unable to work with people in Congress."

Healso stressed the importance of turnout, telling supporters inside theIowa Events Center in Des Moines to get "everyone we know" to the polls.

"Gotta get that done!" Romney said as the crowd of 4,440 enthusiasticsupporters cheered and applauded. "This is a huge; this is a hugeturnout, and what makes this rally and all your work that much moreinspiring is because you're doing it because you care about America."

This could be particularly important in Iowa or Romney. A new Des Moines Register poll released Saturday gave Obama a 5-percentage-point lead - 47% to 42%. It was Romney's second rally in Iowa in two days.

Iowa,like several swing states, has seen its economy improve over the lastfour years - a trend that Obama will likely point out during his finalrally in the state Monday.

But Romney surrogate, Gov. TerryBranstad, said the improvement had nothing to do with the presidentduring his remarks at the rally. "If Obama wants to take credit for theeconomy let him take credit for it in Illinois - but not Iowa,Wisconsin, Michigan, Indiana, Ohio - the Republican governors areleading the way," Branstad said.

With an eye toward undecidedvoters - women and independents in particular - Romney is vowing to workclosely with "good Democrats" if elected. The pledge of bipartisancooperation fueled Obama's candidacy four years ago. But for Romney, thebipartisan appeal became the focus of his campaign in recent weeks.

"OnNov. 6 we're going to come together for a better future. On Nov. 7,we'll get to work," Romney said in Iowa. "You reach across the street tothat neighbor with the other yard sign. And I'll reach across the aisleto people in the other party, people in good faith, because this timedemands bringing America together."

His campaign would not saywhether Romney's transition team, which has already begun to craftlegislation designed for release on his first day in office, has reachedout to Democrats on Capitol Hill.

"I don't think there's been anyoutreach," Madden said aboard Romney's campaign plane Sunday. "Once wewin, I think the governor is going to do his best to work with as manyfolks as possible."