BIRMINGHAM, Ala. (AP) The promised third dramatic comeback this was not.

Newt Gingrich's defeats in his must-win home region of the Deep South on Tuesday ensure that his White House bid is all but over even if he refuses to acknowledge as much.

The stubborn former House speaker is vowing to stay in the race even though he's low on cash and facing pressure to step aside after losses in Mississippi and Alabama. In doing so, he could end up damaging his legacy in a party he helped build. Yet that seems to be a risk he's willing to take, for now at least.

"Why would I walk off from my party and leave them with two people who can't win?" Gingrich recently told The Associated Press. He insisted he would stay in the contest even if he lost in the region that's home to Georgia, which he represented in Congress for two decades.

It's been a rollercoaster of a campaign for Gingrich, who entered the race a year ago only to watch his campaign implode weeks later. He spent last summer laying low, only to surge in the weeks before the Iowa caucuses Jan. 3. He didn't win them but managed to rise again to win the South Carolina primary on Jan. 21. He endured six weeks of losses before crushing his rivals in his home state of Georgia. He then looked to neighboring Southern states for a third and final rebirth.

But it didn't happen.

Gingrich finished second in both Mississippi and Alabama behind Rick Santorum, who cemented his place as the preferred conservative alternative to GOP front-runner Mitt Romney. The losses blew a 400-mile wide hole in the former Georgia lawmaker's plan to stitch together victories across the South, the heart of the GOP base.

Publicly undeterred, Gingrich and his wife, Callista, traveled to Illinois on Wednesday to campaign there ahead of its primary next Tuesday, and he's promising to take his fight to the party's national convention in Florida in late August.

"He believes he can do this. But he and Callista are probably the only two people who believe it," said former top Gingrich aide Rich Galen, a GOP strategist. Still, Galen warned that Gingrich's status as an elder statesman of the party could take a hit if he continues his campaign much longer. "It makes him look foolish."

Two and a half months into the state-by-state voting, the two biggest questions hanging over the race are whether Gingrich drops out and whether his largest financial backer casino titan Sheldon Adelson will continue to open his wallet for a pro-Gingrich super political action committee that has run millions of dollars in TV ads on his behalf.

Santorum and Romney are locked in a two-man delegate fight that could stretch well into the summer. Gingrich and Texas Rep. Ron Paul have been pushed to the sidelines given their lack of victories. Gingrich has won only two of the roughly two dozen states that have voted; Paul has won none.

Romney, a former Massachusetts governor, is on pace to reach the 1,144 delegates needed to clinch the nomination in June. And despite winning Tuesday, Santorum, a former Pennsylvania senator, cannot catch him, and Gingrich is not expected to come close if Romney continues to amass delegates at his current pace. Their only chance is to prevent Romney from reaching the needed delegates and then force a fight at the August convention.

A day after Gingrich's losses, advisers rejected the notion that the race was down to Romney and Santorum.

"You are joking," Gingrich adviser Tony Dolan said and insisted: "It's a three-way dynamic."

Gingrich aides argue that he can still win the nomination before the convention by racking up uncommitted delegates who could decide to back him.

They also said nominating contest has yet to reach its halfway point and that a strong second-half performance by Gingrich could sway those uncommitted delegates to his campaign.

Gingrich's campaign issued a strategy memo this week noting that Louisiana, which holds its primary on March 24, is friendly territory, as is Washington, D.C., where Santorum is not on the ballot, Maryland and Wisconsin, the childhood home of Callista Gingrich. All three hold their contests on April 3.

Allies noted Gingrich's storied career of returning to prominence as one of the nation's leading Republican figures after crushing public defeats.

"His resilience reminds me that his greatest asset might be his durability. It reminds me of Nixon, Clinton and Reagan," said longtime Gingrich adviser Craig Shirley, referring to eventual presidents who triumphed after political defeats. "These guys have an indomitable spirit."

Gingrich rose to become House speaker in 1995 after leading the first Republican takeover of the House 40 years. But he left just a few years later under a cloud of questions about his ethics, and has used the presidential campaign to help return him to prominence within the party.

Gingrich repeated at the first of a series of Illinois stops Wednesday his promise of "getting to Tampa" for the Republican National Convention, but acknowledged the race was taking a toll.

"This is a very challenging campaign," he told about 100 people in Rosemont near Chicago. "It is particularly challenging because I am campaigning on very new ideas that are very different."

Even as he vows to press on, Gingrich has started talking almost wistfully about the campaign.

He told the AP that while he was not bothered, or deterred, by calls for him to quit the race, he was hurt by them last summer after a mass exodus from the campaign by top advisers and staff over strategy and financial disagreements.

"That was painful. That was a point where I said, 'I've been active in this party since the summer of 1960. I think it's fair to say I helped grow the Georgia Republican Party and I helped grow the national majority,'" Gingrich said last week. "I'm a genuine outsider mobilizing the American people against the Washington establishment of both parties. That's fine with me."


Associated Press writer Brian Bakst in Rosemont, Ill., contributed to this report.

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