WASHINGTON (AP) — A day after Herman Cain shuttered his Republican candidacy for president, struggling GOP hopefuls looked to pick up the fallen candidate’s tea party following and upset a primary dynamic that has pushed Mitt Romney and Newt Gingrich to the forefront.

Gingrich’s campaign, ramping up its operations in early nominating states, was meeting with former Cain aides and advisers now looking for jobs. While Cain’s endorsement remained up for grabs, Gingrich and his rivals were looking to schedule one-on-one meetings this week with the former pizza executive.

Reps. Ron Paul of Texas and Michele Bachmann of Minnesota said Sunday they expected Cain supporters would fall in line behind them because of their messages on limited government, despite their low standing in the polls. Meanwhile, last-place rival Rick Santorum predicted he now had a good chance of winning the Iowa caucus.

While such brazen predictions are probably overstated, the 11th-hour press comes at a crucial time and could upset an already volatile race for the GOP endorsement. A month before the first vote is cast in the Iowa caucus and five weeks before the New Hampshire primary, most GOP candidates were looking to a week of heavy campaigning in Iowa ahead of the next debate, scheduled for Saturday. The stakes are possibly the highest for Mitt Romney, who could be hurt the worst if Cain supporters rally behind Gingrich.

“A lot of Herman Cain supporters have been calling our office and they’ve been coming over to our side,” said Bachmann. “They saw Herman Cain as an outsider and I think they see that my voice would be the one that would be most reflective of his.”

Likewise, Paul said he was optimistic that Cain’s departure would reinvigorate his campaign.

“We’re paying a lot of attention to that, because obviously they’re going to go somewhere in the next week or so,” Paul said of Cain’s supporters.

Santorum predicted that his campaign would pick up steam in coming days.

“We have a very strong, consistent conservative message that matches up better with Iowans than anybody else. And we think we’re going to surprise a lot of people,” he said.

Once surging in the polls, Cain dropped out of the race Saturday after battling allegations of sexual harassment and a claim that he had a 13-year extramarital affair. The Georgia businessman has denied the accusations.

Gingrich, the former House speaker from Georgia, has so far been the biggest beneficiary of Cain’s slide. A Des Moines Register poll conducted Nov. 27-30 and released late Saturday found the former House speaker leading the GOP field with 25 percent support, ahead of Paul at 18 percent and Romney at 16.

A separate NBC News/Marist poll showed Gingrich beating Romney, 26 percent to 18 percent, among Republican caucus attendees in Iowa.

Gingrich also is enjoying national popularity that could give him the momentum he needs to overcome deficiencies in the organization of his campaign. At the same time, Gingrich says he knows his surge in the polls could disappear if his opponents stage a comeback.

“I’m not going to say that any of my friends can’t suddenly surprise us,” Gingrich said at a recent town hall meeting in New York sponsored by tea party supporters.

Meanwhile, Romney is running strong in New Hampshire, which holds the nation’s first primary on Jan. 10. Romney is also seen by most conservatives at this point as having the greatest chance of defeating President Barack Obama next year.

But Romney continues to be viewed with suspicion by many conservatives who say he has changed his stance on such critical issues as abortion and health care. Santorum acknowledged Sunday that Romney has embraced more conservative positions on issues.

“The question is, you know, what’s the sincerity of the move and whether he can be trusted,” said Santorum.

Bachmann said it was too soon to declare anyone a true front-runner because the dynamic in the race was constantly changing.

“We’ve got 30 days,” she said. “That’s an eternity in this race.”

Reince Priebus, the Republican Party chairman, said Sunday that he was indifferent to Cain’s departure and that it was “only natural” in the face of falling poll numbers and trouble raising money.

This week’s agenda for the primary candidates included a stop in Arizona by Romney and a forum Wednesday by the Republican Jewish Coalition in Washington, which is expected to attract Bachmann, Gingrich, Huntsman, Perry, Romney and Santorum. Gingrich was scheduled to meet Monday with real-estate mogul Donald Trump at Trump’s New York offices. Trump, who briefly entered the primary race in the spring and drew considerable publicity when he questioned the validity of Obama’s birth certificate, said he would moderate a Republican presidential debate in Iowa on Dec. 27.

Paul, who has clashed publicly with Trump, said he thought the GOP was making a mistake in giving Trump so much credibility.

“I don’t understand the marching to his office. I mean I didn’t know that he had an ability to lay on hands, you know, and anoint people,” Paul said.

Paul and Bachmann spoke on CNN’s “State of the Union.” Santorum spoke on ABC’s “This Week.” Priebus spoke on NBC’s “Meet the Press.”

Copyright 2011 The Associated Press.