Why Jeb Bush's Nod Is the Beginning of the End of the Primary Race

It’s the ninth inning of the Republican presidential primary, and Mitt Romney just brought his ace closer into the game. Former Florida Gov. Jeb Bush’s support of the GOP front-runner, one of the race’s most coveted endorsements, sends an unequivocal message to Republicans everywhere that after a long, bitter primary fight, it’s time to unite behind Romney as the party’s presidential nominee.

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Bush’s imprimatur won’t strong-arm conservative insurgent Rick Santorum out of the race, but, coming a day after Romney’s commanding victory in the Illinois primary, his support leaves the ex-senator from Pennsylvania suddenly in desperate need of another primary victory to maintain credibility.

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“Primary elections have been held in thirty-four states, and now is the time for Republicans to unite behind Governor Romney and take our message of fiscal conservatism and job creation to all voters this fall,” Bush said in a surprise statement sent Wednesday morning. “I am endorsing Mitt Romney for our Party’s nomination. We face huge challenges, and we need a leader who understands the economy, recognizes more government regulation is not the answer, believes in entrepreneurial capitalism and works to ensure that all Americans have the opportunity to succeed.”

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Romney had locked in most of the GOP establishment after Texas Gov. Rick Perry’s campaign collapsed and New Jersey Gov. Chris Christie declined to make a surprise late entrance into the race. But support from the former governor, son of former president and fellow Romney endorser George H. W. Bush, could bring a second wave of endorsements from GOP officials who have thus far stood on the sidelines, according to Phil Musser, a GOP strategist and Romney supporter.

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The list Musser ticked off included Indiana Gov. Mitch Daniels and former Mississippi Gov. Haley Barbour, two powerful figures in the conservative movement who might be swayed by a former colleague who has both policy bona fides and access to the vast Bush finance and grassroots networks. “I think Jeb has enormous credibility, particularly with Republican governors,” Musser said. “I think his endorsement sends a strong signal to people to get behind Romney, that it’s time to coalesce.”

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A united front by GOP bigwigs could choke off fundraising and support for Santorum, who is already struggling against the widespread perception of Romney’s inevitability. Tuesday’s double-digit defeat in Illinois was another contribution to the political zeitgeist that Santorum is only playing spoiler if he stays in the race.

Even Erick Erickson, founder of the conservative blog RedState.com and an ardent Romney critic, conceded Wednesday that the former Massachusetts governor will be the party’s nominee. “Conservatives may not really like Mitt Romney, but they do not want a fractured party too divided to beat Barack Obama. There will be no white knight, no dark horse, and no brokered convention. We have our nominee,” he wrote.

Santorum has a chance at a victory in socially conservative Louisiana, which holds its primary Saturday. He could enhance his credibility even more if he wins Wisconsin, which where Republicans vote April 3. But while Louisiana is a Deep South state where Santorum is heavily favored, Wisconsin closely resembles Midwest states like Ohio and Michigan, where Romney has triumphed. And most of April, including Maryland, Delaware, Connecticut, Rhode Island and New York, is friendly Romney territory.

Whether Jeb Bush’s endorsement will be as important among voters as it is with the Republican establishment is uncertain. The former governor, a pragmatist who performed well among moderate voters in Florida, reinforces the notion that Romney’s base lies in the party’s upscale, secular wing, where he has run up huge margins thus far in the primary. It’s less clear if Bush can help Romney among the voters he has struggled to court, the conservative evangelicals who have coalesced around Santorum. The GOP’s tea party wing might even be turned off by, and less inclined to back, a candidate who continues to pile up establishment support. That was the populist-flavored talking point embraced Wednesday by those who hope to derail Romney.

Santorum said the race was coming down to “the establishment, the money, versus the people” and him. Asked in Harvey, La. if was time for the party to come together, he responded: “I agree, they should all start supporting me because I'm the strong conservative candidate . As we’ve seen in every state, all the endorsers, the establishment, who is comfortable with the status quo, go with Mitt Romney. And the folks who want to see the real changes going on in D.C. support me."

R.C. Hammond, a spokesman for Newt Gingrich, called Jeb Bush’s move “the completion of the establishment trifecta.” It was an allusion to earlier Romney endorsements by Bush senior and former GOP presidential nominee Bob Dole.

The insurgents can take heart from Republican voters, who have signaled they’re not quite ready to end the primary process even if many GOP officials are. According to exit polls from the Illinois primary, two-thirds of voters want to the campaign to continue instead of seeing their candidate claim the nomination. That even includes about half of the Republicans who voted for Romney.

Lindsey Boerma and Sarah Huisenga contributed.