Former sports czar Peter V. Ueberroth, who built a career out of making the seemingly impossible happen, on Tuesday ended his longshot bid to become California's next governor, saying there wasn't enough time left "for this candidacy to get across the goal line."

It was not immediately clear how his departure would affect the balance of the race beyond winnowing the list of top contenders and better defining the battle.

Although he is a Republican, Ueberroth was running as a centrist with bipartisan appeal, and the three top remaining candidates moved quickly to lay claim to his supporters.

Three hours after Ueberroth's announcement, state Sen. Tom McClintock asserted that he was gaining momentum and challenged fellow Republican Arnold Schwarzenegger to a "real Lincoln-Douglas debate."

Ueberroth's campaign said his decision to quit was not tied to the release of Field Poll results Monday that showed him drawing support from only 5 percent of likely voters and trailing the leaders, Democratic Lt. Gov. Cruz Bustamante and Schwarzenegger, by at least 20 percentage points.

Given Ueberroth's relatively low standing in the polls, his departure isn't likely to give much of a bump to anyone, some analysts said.

"I wouldn't guess that it will have a huge impact, frankly," said Walter Stone, chairman of the political-science department at the University of California, Davis. While it is unclear where Ueberroth's supporters might go, "there just aren't enough of them to make a huge difference."

What could be more significant is whom Ueberroth endorses. He declined Tuesday to back any of his competitors, saying he intended to meet with the main contenders to find out who would best push his agenda to resolve the state's budget crisis through job creation.

"He's still highly respected in Southern California, and his endorsement could have an impact on how people vote," said Allan Hoffenblum, a Republican strategist.

Ueberroth, the architect of the 1984 Los Angeles Olympics and former baseball commissioner, pledged to work with any governor to resolve the state's financial problems. That offer included Gov. Gray Davis, should he survive the Oct. 7 recall, although Ueberroth said he still supported the recall, did not consider Davis to be a candidate and would not consider endorsing him.

Despite quitting, Ueberroth said he felt as if his campaign had been beginning to catch on with voters. The problem was the calendar, shortened by his own last-minute decision to run.

"We're not going to be able to climb the mountain fast enough," he said.

Ueberroth, the third major Republican to drop out of the race after recall financer Rep. Darrell Issa and Bill Simon, was the second leading money-raiser among the 135 original candidates. On Tuesday, he promised the equivalent of a money-back guarantee to his supporters. He said he would return the more than $2.1 million contributed to his campaign -- largely by friends and business acquaintances -- and pay all the bills himself, a tab aides said would exceed $2 million.

In a campaign marked by sharp words, reaction to Ueberroth's decision was gracious. Schwarzenegger and McClintock issued statements lauding Ueberroth for running a positive campaign focused on issues, and each sought to align their campaigns with Ueberroth's budget-focused theme.

Schwarzenegger described Ueberroth's short run as "another chapter in a long and distinguished career."

"He has been a force for good, particularly his determination to focus public attention on the need to strengthen our economy if we are to restore the fiscal health of our state," Schwarzenegger said. "We share core beliefs about the urgent need to restore the economic vitality of California, and about the important steps that will achieve that result."

McClintock said he was "personally saddened" by the decision.

"He is an exceptionally qualified and capable candidate whose expertise will be missed in this campaign," McClintock said. "His withdrawal intensifies my resolve to stay the course. It is essential that the people of California have a candidate who knows and understands the complexities of state government and who has the determination to defeat the spending lobby that controls it."

Bustamante called Ueberroth "a gentleman," said he would like "to sit down and talk to him about his ideas for job creation in California's economy" and claimed the departure would help his own campaign.

"I think the person who is looking at a Ueberroth candidacy is looking for people who are having clear, decisive ideas," Bustamante told reporters in Los Angeles after taking part in a candidate forum. "I think I've been able to do that, and I'm hopeful it will be able to help me."

Even Davis's campaign found positive words for someone who had been trying to take the governor's job.

"Peter Ueberroth is a well-respected Californian who has made an enormous contribution to the civic life of our state," said Peter Ragone, spokesman for Davis's anti-recall campaign. "We know he will continue to play an important role in our state for years to come."

During his brief run, Ueberroth stuck firmly to a pledge that he would be a positive campaigner focusing on issues.

"We have very little doubt that, had this been a more normal extended campaign cycle, there would been more than enough time for voters to hear a positive, substantive and detailed message," campaign manager Dan Schnur said.

Ueberroth sought to cast himself as the perfect candidate to deal with the state's fiscal woes, pledging to serve only until the end of the term, collect no salary as an austerity symbol and dedicate himself single-mindedly to fixing the budget and creating jobs.

But Ueberroth's campaign never seemed to get started. He campaigned sporadically and often seemed ill-at-ease on the trail, although in close contact with voters and supporters he could be warm and engaging.

In a telephone interview Tuesday, Ueberroth said that, although he would not run for governor again, he still hoped to involve himself in public service. And he said although the outcome wasn't what he had hoped, he enjoyed the experience and learned much.

"I don't know what it's training me for," he said, "but it's been a great learning curve."