WASHINGTON (AP) – The rising profiles of Republican presidential candidates Rick Perry and Michele Bachmann are giving the White House a new opening: linking the entire GOP field to the tea party, whose popularity has recently sagged.

If the strategy works, it could cause guilt-by-association problems even for non-tea-party Republicans like Mitt Romney.

That might be a lot to ask, however. Unflattering comparisons are a well-worn campaign tactic, and many Americans have only a hazy notion of the tea party movement. Still, President Barack Obama’s top aides are giving it a go.

Republican candidates must decide whether to “swear allegiance to the tea party” or work with Democrats to create jobs, Obama campaign adviser Robert Gibbs said Tuesday. After last week’s GOP debate in Iowa, Obama campaign guru David Axelrod claimed the presidential contenders were “pledging allegiance to the tea party.”

And a new video by the Democratic National Committee says Republican lawmakers and presidential candidates are “embracing extreme tea party policies.”

Democrats first aimed such barbs at congressional Republicans, who hewed closely to tea party demands in shaping a debt-ceiling bill this month. It was harder to target the presidential field as long as attention centered largely on former governors Romney, Tim Pawlenty and Jon Huntsman. All three are conservatives but not from the tea party mold, which places greater emphasis on uncompromising demands for unusually deep cuts in government spending and oversight.

A quick succession of events changed that over the weekend.

Bachmann, the House member from Minnesota who chairs Congress’ tea party caucus, won an Iowa straw poll. Pawlenty ended his campaign, and Perry, the Texas governor with tea party leanings, jumped in.

Romney, whose presumed GOP front-runner status looks shakier than before, is responding by edging toward tea party positions, opening himself to the Democrats’ broad-brush criticisms.

At last week’s Iowa debate, for instance, Romney joined all the others in saying he would reject a debt-reduction package if it included as much as $1 in tax increases for every $10 in spending cuts.

“That’s just not common sense,” Obama told a Minnesota crowd on Monday.

The grass-roots, decentralized tea party movement sprung to life in 2009 to oppose Obama’s health care initiative, then swung its focus to cutting taxes and spending. It helped Republicans win huge victories in 2010, and now it’s playing an early and potent role in the GOP presidential process.

As the movement asserts its clout, however, its popularity has dropped.

A recent New York Times/CBS News poll found that 40 percent of American adults had a “not favorable” view of the tea party, compared with 18 percent in an earlier poll. The proportion who said they knew too little to form an opinion of the tea party fell to 21 percent, from an earlier 46 percent.

At the same time, Obama’s approval ratings also have slumped, and Congress’ have hit an all-time low.

Tying a political opponent to a not-so-popular person or movement is a hit-or-miss strategy, said John J. Pitney Jr., a political scientist at Claremont McKenna College. Bill Clinton’s 1996 re-election campaign ran ads against “DoleGingrich.” The goal was to link GOP nominee Bob Dole to Newt Gingrich, then the embattled House speaker, and now a presidential candidate.

The tea party could be a tougher target, Pitney said. “A diffuse movement with no clear leader does not arouse the same kind of emotion,” he said.

Mike DuHaime, who managed Republican Rudy Giuliani’s 2008 presidential campaign, said the Democrats’ tactic might succeed so long as Romney and the other GOP candidates seem to be toeing the tea party line.

“The strategy is sound for the Obama team because they would love the campaign to be about the challenger, no matter who it is,” DuHaime said. “To the extent that our candidates continue to essentially march in lockstep with each other on major issues, it will be easy for the Obama campaign to paint them all with the same brush.”

Obama had a rare direct brush with a tea partyer this week while shaking hands in Iowa. Activist Ryan Rhodes complained about reports that Vice President Joe Biden had said tea partyers acted “like terrorists” in the debt-ceiling showdown.

Obama said Biden “was objecting to us almost defaulting” on U.S. debts. When Rhodes persisted, Obama told him “it doesn’t sound like you are interested in listening.”

Earlier, the president portrayed himself as a pragmatic problem-solver who might appeal to independent voters wary of the tea party’s conservative fervor.

“I make no apologies for being reasonable,” Obama told the Iowa crowd.

Copyright 2011 The Associated Press.