President Obama’s re-election campaign launched an opening attack on Republican presidential frontrunner Mitt Romney on Wednesday, painting the former Massachusetts governor as a flip-flopper whose economic plans would harm the middle class.

The criticism from senior campaign strategist David Axelrod was a tacit acknowledgment from the Obama camp that Romney is separating himself from the rest of the Republican field and represented an attempt to begin shaping a public counter-narrative about him. Many political analysts have said Romney would have the best chance to beat Obama among the current candidates.

Axelrod blasted Romney for calling Obama’s proposal to extend a payroll tax cut a “little Band-Aid” during a Republican candidate debate Tuesday night sponsored by the Washington Post and Bloomberg. Romney said he would prefer permanent changes to the tax code rather than Obama’s temporary extension.

Noting that the payroll tax cut would mean an extra $1,500 for the typical family, Axelrod said that Romney’s opposition "does not inspire trust, it inspires questions. And those questions will grow over time.”

During a 20-minute conference call with reporters, Axelrod delivered a sustained attack on Romney by charging that he has taken conflicting positions on issues ranging from health care to taxes to the debate over Chinese currency ma­nipu­la­tion.

“If this were one time, you might say it was a momentary lapse, but it was a pattern time and time and time again,” Axerod said. “You heard it again last night. It’s consistent with a guy who ran for the governorship and the Senate in Massachusetts as a pro-choice moderate who supported civil unions and supported environmental protections to the guy you see today hard after the Tea Party vote who has thrown all his positions over.”

Axelrod continued: “Across the political spectrum, people have the same question: If you are willing to change positions on fundamental issues of principle, how can we know what you would do as president? How can we trust who you would be?”

Romney’s camp fought back by charging that the Obama team was aiming to obscure the more important issue: the administration’s policy failures on the economy

“What we’re getting from this administration in response to the tanking economy are deflections and diversions from what really matters, which is President Obama’s failure to create jobs,” said Ryan Williams, a Romney spokesman. “President Obama has turned America into an economic disaster zone. The only question is whether we can make it to the election of 2012 before Obama takes us all the way back to 1929.”

Axelrod’s comments echoed an attack campaign already underway by the Democratic National Committee, which has established a Web site and YouTube channel called “Which Mitt” and catalogues his sometimes conflicting statements on various subjects, including abortion rights.

Reporters noted that Romney’s Republican rivals for the nomination also have attempted to paint him as a flip-flopper to no avail, as Romney remains atop the polls. Axelrod scoffed, saying that while Texas Gov. Rick Perry tried to make the attack, he “never got his gun out of his holster.” Perry famously fumbled the attack during a previous debate.

“I will give him this,” Axelrod said of Romney, “he is as vehement and as strong in his convictions when he takes one position as he is when he takes diametrically opposed positions. That’s something that in the short term you can get rewarded for. George Burns, the old comedian, once said that all you need to succeed in show business is sincerity and if you can fake that, you’ve got it made. There’s something to that in politics, as well. But I don’t think you can do that in a presidential campaign. People want to know who you are, what you believe in, what you stand for.”

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