As Santorum fades, Mitt Romney attacks Obama for flip-flopping

Mitt Romney now leads Rick Santorum in his home state of Pennsylvania, a new poll shows. And Romney is accusing Obama of flip-flopping on issues.

 Likely Republican nominee Mitt Romney and President Barack Obama have begun testing lines of attack as they prepare for an expensive and arduous political battle over the seven months between now and the Nov. 6 election.

Romney made news Wednesday by accusing Obama of abandoning 2008 campaign promises for political expediency once in office. It was an unexpected assault by the candidate who is himself under fire in his own party for the ease with which he has changed positions to appeal to the ultra-conservative Republican base.

Romney, who held moderate positions when he won the governorship in Massachusetts 10 years ago, has shifted hard to the political right in his bid for the party nomination. He has been sharply criticized by top challenger Rick Santorum and other Republican rivals for changing his positions on issues ranging from abortion to climate change.

Earlier this year, he reversed course on the minimum wage to bring his stance in line with party orthodoxy, saying he no longer believes it should rise along with inflation. The federal minimum wage law sets a floor under hourly rates for low-paying jobs.

Meanwhile, a new poll shows that Mitt Romney now leads former Sen. Rick Santorum in his home state of Pennsylvania.A new poll by Public Policy Polling shows among likely GOP primary voters, Romney gets 42 percent, while Santorum pulls in 37 percent. Romney's numbers have jumped by 17 points in the last month. The Pennsylvania primary is April 24.

But Romney is clearly shifting his focus away from his GOP contenders. On Wednesday, Romney said Obama had undergone his own "series of election-year conversions" on taxes, government regulation and energy production.

He also told an audience of newspaper editors and publishers that Obama had called "his candor into question" in recent remarks to Russian President Dmitry Medvedev about having greater flexibility in a second term to negotiate further arms control pacts.

"What exactly does President Obama intend to do differently once he is no longer accountable to the voters? With all the challenges the nation faces, this is not the time for President Obama's hide-and-seek campaign," Romney said.

The bulk of Romney's remarks amounted to a rebuttal to Obama, who spoke from the same stage on Tuesday to the annual meeting of The Associated Press. The president criticized a Republican budget, passed in the House of Representatives and supported by Romney, as a radical vision for changing the American social contract. Obama poked fun at Romney's description of the budget as "marvelous."

Romney said Wednesday that instead of laying out plans for a second term, Obama "railed against arguments no one is making — and criticized policies no one is proposing. It's one of his favorite strategies, setting up straw men to distract from his record."

Despite skepticism by some in his own party, Romney appears on course to collect the needed 1,144 delegates — chosen in state-by-state primary elections and caucuses — by late June for the Republican nomination. The party officially names its nominee at a national convention in August.

While falling further behind, Santorum has vowed to stay in the race despite calls by Romney and others to end his campaign so Republicans unite behind him.

The candidates face a three-week primary intermission before the next contests in Pennsylvania, New York, Delaware, Connecticut and Rhode Island.