President Barack Obama has launched his re-election bid in a low-key manner, but the Republican Party’s search for a challenger seems stranger by the day.

GOP celebrities like Sarah Palin aren’t getting much buzz. Mainstream candidates like Mitt Romney and Tim Pawlenty aren’t getting much traction. It’s people once considered highly unlikely to compete seriously for the party’s nomination who are creating big stirs in early voting states, a reflection of an unformed and uncertain GOP presidential field.

Republican activists in Iowa, New Hampshire and South Carolina appear deeply intrigued by, and open to, a run by Donald Trump, the publicity-loving business tycoon and host of NBC’s "The Apprentice," even as he perpetuates falsehoods about Obama’s citizenship and questions the legitimacy of his presidency.

"I hear more and more people talking about Donald Trump," said Glenn McCall, Republican Party chairman in South Carolina’s York County. "He’s got people fired up."

These Republican officials and activists stopped short of saying they see Trump as the eventual nominee. But they said their party is hungry for forceful, colorful figures to attack Obama and other Democrats on health care, spending and other issues.

In Iowa at least, there’s also widespread talk about two social conservatives: Rep. Michele Bachmann of Minnesota, who would be the first president elected directly from the House since James Garfield, and former Pennsylvania Sen. Rick Santorum, who lost his 2006 re-election bid by a landslide. Even Herman Cain, the little-known, wealthy former pizza chain executive, gets mentioned by Republican voters who will have the first crack at winnowing the GOP field.

While these people certainly have talents, the party’s establishment does not see them as the likeliest contenders to defeat Obama. Karl Rove, architect of George W. Bush’s two presidential wins, calls Trump "a joke candidate."

Republicans traditionally pick party veterans who wait their turn and earn their nominations after years spent as governors, senators or vice presidents. But this field lacks a front-runner like Bob Dole in 1996 or George W. Bush in 2000. There’s a political vacuum in the GOP, insiders say, and it’s being filled by an unusually large and diverse number of White House hopefuls.

"It’s probably the most wide open field in 50 years," said Stephen Scheffler, a Republican National Committee member and head of the Iowa Faith and Freedom Coalition. "I’m not sure anyone has caught fire yet."

South Carolina Republican Party chairwoman Karen Floyd said, "It’s any candidate’s ballgame right now." Kim Lehman, another RNC member from Iowa, said voters haven’t locked in on any one person. "Everyone is taking their time and seeing who’s who, and what’s what," she said.

Palin’s apparent fade and Trump’s rise are arguably the most surprising events in recent weeks, as more establishment-oriented contenders, including former governors Romney of Massachusetts and Pawlenty of Minnesota, took formal steps toward full-fledged candidacies.

A CNN nationwide poll of adult Republicans showed Trump tied for the presidential lead with former Arkansas Gov. Mike Huckabee, at 19 percent each. Palin, the 2008 vice presidential nominee, was third at 12 percent.

A Washington Post-ABC News poll, without suggesting names, asked Republican adults to cite a candidate they would support in a GOP primary. Sixteen percent named Romney, 8 percent Trump, 6 percent Huckabee and 5 percent Palin.

In the full survey of Democrats, Republicans and independents, Obama bested all the potential GOP candidates in hypothetical matchups. His margin over Palin was 55 percent to 38 percent.

This early in the race, polls measure name recognition more than anything else. That may help explain strong showings by Trump and Huckabee. The Arkansas Republican won the 2008 Iowa caucus and hosts a TV show, but has done little to signal he will run again. Trump, meanwhile, is turning heads in early voting states, including Iowa where he’s slated to headline the state GOP’s summer fundraiser June 10.

"He is causing conversations," said Trudy Caviness, the GOP chairwoman in Iowa’s Wapello County.

McCall said Trump "is saying on the national stage what other people won’t talk about."

That includes talking about trade, China and oil dependency. But Trump’s biggest buzz stems from his embrace of the claim that Obama wasn’t born in the United States, and therefore is constitutionally barred from being president.

Documents, including Obama’s birth certificate, show he was born in Hawaii in 1961.

Several Republican activists said they don’t care much about Obama’s birthplace, but they’re tired of waiting for the more establishment-backed challengers to challenge the president often and fiercely. For some, Trump fills that void.

For his part, Trump declined Tuesday to back away from the questions he has raised about Obama’s citizenship, saying in an interview broadcast on NBC’s "Today" show that it’s a legitimate subject.

Trump also said he opposes increasing the nation’s debt limit, even though experts have said that could cause the government to default on its debts. "I wouldn’t raise it," he said. "You’re going to have to make a (political) deal someplace. You might as well do it right now. I’d do it right now. I’d stop it right now."

In New Hampshire, Republican activist Phyllis Woods of Dover said she was surprised by the commotion Trump is causing. "Whether Donald Trump is going to be taken as a serious candidate here is an open question," she said. What is certain, she said, is that "we’re going to have a huge field."

Woods said she detects "a growing undercurrent of support" for Bachmann, a comment echoed by several Iowa and South Carolina activists. "She is a fresh face and a fresh voice," Woods said.

Bachmann seems to have eclipsed Palin as the most discussed, if sometimes gaffe-prone, provocateur among tea party conservatives.

Democratic strategists and Obama supporters watch these developments with bewilderment, and a vague sense that they won’t last. They say they can’t predict who will be the nominee, but more traditional candidates such as Romney, Pawlenty or Mississippi Gov. Haley Barbour seem more plausible than, say, Trump. Political insiders would not be stunned if Bachmann won the caucus in her native Iowa, and Gingrich could do well in places, including South Carolina.

Not all GOP insiders embrace Trump.

"You’ve got Donald Trump on TV making a fool of himself," said Leigh Macneil, the Republican chairman in New Hampshire’s Merrimack County. Macneil said Trump is filling a regretful vacuum because more mainstream candidates are holding back. "We’re looking for people who will step up," he said. He wishes more outspoken, forceful candidates would jump in, especially New Jersey Gov. Chris Christie and Indiana Rep. Mike Pence.

"My dream ticket would be Christie-Pence," Macneil said.

Others seem happy with their choices.

"It’s a wide open field," and that’s fine, said Kathy Pearson, a longtime party activist in Cedar Rapids, Iowa. She said Trump is "a TV celebrity and obviously a successful businessman" who is "saying what he thinks."

"What’s going on right now is very good, very healthy for the process," said Cindy Costa, South Carolina’s Republican National Committeewoman. Voters want "someone who is a good leader and understands business." She has long admired Romney, she said, and "I’ve been pleasantly surprised" by Trump. "He’s actually more conservative than I had thought."

Trump’s three marriages don’t seem to be a major issue among conservatives, for now at least.

"All his ex-wives are happy," said Joni Scotter, a Republican activist from Marion, Iowa. Ordinarily, she said, GOP caucus voters "are hard on people who are divorced."

She said she hopes the thrice-married Gingrich receives the same generosity.