Mitt Romney has overtaken Rick Santorum in his GOP rival's home state of Pennsylvania, a new poll released Thursday shows.
Romney is leading the former Pennsylvania senator 42 percent to 37 percent. Ron Paul is at 9 percent and Newt Gingrich has 6 percent of the vote, according to the survey from Public Policy Polling.
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In the same poll taken one month ago, Santorum led Romney 43 percent to 25 percent, The Hill reported.
Public Policy Polling notes in its analysis that just over a third of GOP voters still think Santorum has a chance at capturing the party nomination, while more than half think he's out of luck. And Romney's favorability has increased in recent weeks, PBS reported.
Karl Rove, a former strategist for President George W. Bush, called Santorum a "fading candidate" in an opinion piece Thursday for the Wall Street Journal and shot down Santorum's argument that a prolonged nomination race would energize the party ahead of the general election, according to Reuters.
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"That's the argument of a desperate candidate. More and more Republicans think such a bloodletting would severely set back the cause of defeating Barack Obama," Rove wrote.
Romney continued to canvass Pennsylvania on Thursday, while Santorum is taking a few days off the campaign trail for Easter and won't be back in his home state until Monday, The Hill reported.
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Pennsylvania is one of five northeastern states holding primaries on April 24. The group includes New York and Connecticut, where Romney, a former governor of nearby Massachusetts, has been favored to win.
The poll comes the day after President Barack Obama criticized Romney by name for the first time, mocking his embrace of the House Republican budget from Rep. Paul Ryan, CNN reported.