Former Florida governor Jeb Bush announced his support for Mitt Romney’s presidential bid this morning, a major boost for the former Massachusetts governor as he seeks to rally the party behind his candidacy.

“Congratulations to Governor Mitt Romney on his win last night and to all the candidates for a hard fought, thoughtful debate and primary season,” Bush said in a statement released by his office on Wednesday morning. “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. I am endorsing Mitt Romney for our Party’s nomination.”

Bush followed that statement with this tweet:

I’ve endorsed @MittRomney. It’s time for GOP to unite & take our message of fiscal conservatism & job creation to all voters.

— Jeb Bush (@JebBush) March 21, 2012

Not surprisingly, former Pennsylvania senator Rick Santorum dismissed the Bush endorsement. “The establishment, who is comfortable with the status quo, go with Mitt Romney and the folks who want to see see the real changes going on in DC, support me and I think that’s what this race is coming down to,” he said.

Bush, who spent eight years as the governor of Florida from 1998 through 2006, had avoided making his preference in the primary race known — content to let the process play itself out.

That he picked this moment to wade into the race is clearly meant to send a signal to the Republican party that the time is now to coalesce behind Romney. While others have said that the race is over before, Bush’s decision to call for it to end will hold significantly more weight — and draw significantly more media attention.

“He’s lost any hope that we’ll have anyone better ,” said one senior Republican operative about Bush’s decision to endorse Romney. Added another veteran Republican strategist who occasionally talks to Bush: “I know he wanted to see someone earn it and he had some early foibles with Mitt.”

Not so, according to one source close to Bush. “He feels like the process worked, and now it’s time to come together as a party and focus on the fall,” the source added.

Romney has, by far, the most endorsements in the race from elected officials including former governors Tim Pawlenty (Minn.) and Jon Huntsman (Utah) — both of whom ran against him in the nomination fight — as well as New Jersey Gov. Chris Christie.

He also now enjoys a 300-delegate edge over former Pennsylvania senator Rick Santorum after his 12-point victory in Illinois on Tuesday night.

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