AMES, IOWA - Tim Pawlenty spent more money, locked up more political talent and blitzed the presidential proving ground of Iowa longer and harder than anyone else.

But early Sunday, after reflecting overnight on his distant third-place finish in the Iowa straw poll, Pawlenty abruptly ended a White House quest that has fueled his every move for the past two years.

He was out of gas.

"I'm from a small state. I don't have a big national network, a political network, and so the measure of us in this phase was 'Can you get some lift?'" Pawlenty said on Sunday morning on ABC's "This Week."

The former two-term Minnesota governor, who started his presidential efforts nearly two years ago, said that fundraising would become too difficult and acknowledged that he simply was not what Republicans were looking for.

"I thought what I brought forward was a rational, established, credible, strong record of results, based on experience ... but I think the audience, so to speak, was looking for something different," Pawlenty said.

Pawlenty held an early morning conference call with supporters, expressing his appreciation, but admitting he saw no viable path to victory.

"The governor said he still has the fight in him but didn't have the necessary tools in the toolbox to get the job done," said longtime gubernatorial aide Brian McClung.

Always a struggle, the campaign started to unravel after the first televised GOP debate in New Hampshire in June.

Early in the debate, Pawlenty was presented a primo opportunity to land a direct hit on frontrunner Mitt Romney, whose health care plan he had derided days earlier as "Obamneycare."

But Pawlenty demurred, displaying a moment of weakness from which he never recovered. That, and a chronic inability to excite Republican voters contributed heavily to his disappointing finish in Saturday's straw poll, a dry run for the first-in-the-nation Iowa caucuses five months from now. Fellow Minnesotan Michele Bachmann, a late entry to the race, garnered more than twice as many votes as Pawlenty. So did U.S. Rep. Ron Paul.

"Pawlenty lost the Iowa caucuses in New Hampshire," said Steve Deace, an influential Christian broadcaster in Des Moines.

Too little fire

The obituaries of Pawlenty's once-promising presidential bid will have to say that for all his executive credentials, candidate Pawlenty never managed to deliver the fiery, full-throated conservatism Republicans seem to yearn for.

As the first major candidate to declare, Pawlenty for months rode a wave of Washington buzz. He courted pundits and impressed many by locking up some of the party's top political strategists. But that insider credibility never translated into popular support.

"On paper he looks good," said University of Iowa political scientist Cary Covington. "But he just hasn't caught fire."

Aware of the rising influence of the Tea Party, Pawlenty attempted to vie for their support.

Then came Bachmann.

Pawlenty's game plan, carefully formatted over the past two years, did not foresee the unexpected entry of the Tea Party maven. The Minnesota congresswoman swept into her native Iowa and quickly electrified the deeply conservative straw poll voters in Ames.

Pawlenty, despite once being characterized as the most conservative governor in modern Minnesota history, barely made a ripple, registering in low single digits in polls of Iowa Republicans.

Another stumble may have come in Thursday's debate in Ames, when Pawlenty went after Bachmann's record hard, accusing her of having no legislative accomplishments. She returned fire, questioning his conservative bona fides on health care, the environment and even taxes, comparing him to President Obama.

"She's an effective counter-puncher," observed U.S. Rep. Steve King, an Iowa Republican and Tea Party ally of Bachmann's. "I don't think it helped Pawlenty at all."

Meanwhile, Pawlenty never made any inroads against Romney, the establishment frontrunner who parried the Minnesotan's debate points with dismissive one-line quips.

Rebranding T-Paw

Pawlenty first gained notice as potential presidential timber when he won a second term in 2006 -- a year when many Republicans fell -- by appealing to moderates and independents. But later in his second term he edged further right, shedding earlier, more moderate positions and outright apologizing for others.

As his presidential ambitions grew, Pawlenty worked to craft a profile that could appeal to Republicans further on his right.

He scuffed off his support for environmental programs, which looked too green to many in the GOP, rejected some of his earlier positions on health care and took on an angrier tone than the one that marked his gubernatorial years.

Once he formally launched his bid, he ran a series of slick, super hero-style ads to inject some brio into a persona many called bland. He tried breathing more fire into his speeches, even adopting a seemingly Southern accent in one appearance.

None of it worked.

Amid consistently poor results in state and national polls, Pawlenty doggedly made the case that he was a potential top-tier contender who simply lacked national name recognition. The campaign peddled an image of Pawlenty as the "turtle" in the race who would outlast better known frontrunners who might flame out.

"He's not going to be the flashiest candidate in the race," campaign manager Nick Ayers said before Pawlenty's withdrawal. "So that's why we've never been disappointed by not shooting to the top of the pack."

But Pawlenty's persistent image as everybody's second choice remained.

"It's really too bad that the seriousness in which he approaches politics was perceived by some as a lack of passion," said Minnesota GOP strategist Andy Brehm.

For days Pawlenty's campaign had boasted that its organizational abilities would see it through the straw poll, a fundraising event that requires candidates to draw Republican faithful from across the state to cast ballots in Ames.

But in the end even that failed. Despite all the money and planning, Pawlenty came out only 600 votes ahead of longshot candidate Rick Santorum.

Even before Saturday's vote, "donors were questioning the message or the lack thereof ... he didn't have a clear identity," said a Republican who has long known the governor.

According to long-time advisor Vin Weber, a former Minnesota congressman, it was clear that the money was drying up. In the end, he said, it was a "purely financial decision."

Pawlenty had bet everything -- and spent more than $1 million -- on Iowa, and his path would only have gotten harder in the early voting states of New Hampshire, South Carolina and Nevada.

"He's very good in small settings," said Des Moines attorney Jeff Courter. "But it didn't translate onto the stage."

On the eve of the straw poll, Ayers was asked what it would take to make Pawlenty drop out. "A loss to Buddy Roemer," he joked, in a reference to the longshot former Louisiana governor.

But in the end, the bar was set by Bachmann, who burst on the GOP nominating contest like a Roman candle that eclipsed Pawlenty's star.

Kevin Diaz is a correspondent in the Star Tribune Washington Bureau.