Poll: Obama and Romney virtually tied in swing states of Florida, Ohio, Pennsylvania

President Obama and presumed GOP candidate Mitt Romney are virtually tied in the key swing states of Florida, Ohio and Pennsylvania, according to the latest Quinnipiac University poll. 

In Florida, Romney has 44 percent of voters' support compared with Obama's 43 percent; Ohio has Obama beating Romney just 44 percent to 42 percent; and the President leads in Pennsylvania 47 percent to Romney's 39 percent.

No presidential candidate has won the nomination without winning at least two of the three states polled by Quinnipiac from April 25 to May 1, CBS News reported. Obama won all three in 2008. 

Romney has gained noticeable ground on Obama. Last month, the President had bigger leads in Florida and Ohio, according to an earlier poll by the University. Part of the former Massachusetts' Governor's advantage may come from his stance on the economy: voters in Florida and Ohio said they think Romney would do a better job restoring the American economy than Obama, while just 44 percent of Pennsylvanians say Obama is more apt to pull the US out of its recession, just 1 percent more than Romney's 43 percent. 

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“First, since he is now the de facto nominee, Romney is no longer being attacked by his fellow Republicans who are closing ranks behind him,” Peter Brown, assistant director of the Quinnipiac University Polling Institute in Hamden, Connecticut, told Bloomberg Businessweek. “Second, voter optimism about the economy has leveled off.”

The presumptive GOP nominee is most popular in Florida, where his favorability rating  is 40 percent; Obama is 46 percent. Meanwhile, Romney is most unpopular in Pennsylvania, where 39 percent of those polled view him unfavorably, compared to 43 percent for Obama, according to ABC News.

As for the question of Romney's running mate? 

"Geography is the coin of the realm," Brown said in the poll's statement.

A quarter of Ohio voters say their Senator Rob Portman would be the best choice, while four in 10 Floridians would back their Senator, Marco Rubio. In Pennsylvania, almost a third of those polled favor Governor Chris Christie of neighboring state New Jersey.

"Christie and Rubio do best outside their own neighborhoods," said Brown, "but there is far from any kind of consensus about who would be Romney's best choice."

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