It’s official. This morning, Florida Governor Charlie Crist announced that he is running to succeed Mel Meatinez for the US Senate. The “Obama Republican”, who was one of only a scant handful of Republicans to support Obama’s bailout legislation, quickly emerges as the front-runner in a race that serves as a battleground for what the Republican is to stand for on a national level.

Crist immediately picked up the support of NRSC Chairman John Cornyn, who has the unenviable goal of trying to win back enough seats in the Senate for Republicans to wield a filibuster threat once again. Cornyn has earned the criticism of many conservatives lately for his willingness to recruit and back moderate candidates over conservative Republicans in key elections. In his endorsement today, Cornyn noted Crist’s record in Florida saying that the Governor should, “bring a fresh perspective to Washington in our efforts to fight for lower taxes, less government, and new job creation.”

Erick Erickson, conservative activist and head of RedState, was quick to point out this morning that Crist’s record in Florida may not actually be good for the GOP to run on.

The irony of Charlie Crist’s run is that he is announcing his run today as a Republican and has already committed to raising taxes on working families in Florida. With the GOP’s image already tarnished over its handling of fiscal matters in the past few years, you would think the GOP would be swift to reject someone like Crist. Crist is, after all, the man Barack Obama called his favorite Republican.

You would be wrong.

Politico reports that the conservative base in Florida is restless with Crist and “dissatisfied with his high-profile advocacy for President Barack Obama’s stimulus and his handling of the state’s budget woes.” This is the opening into which Marco Rubio has stepped. Rubio, the former speaker of the Florida House, is described by Erickson as a “young, telegenic conservative reformer,” an image that Rubio has begun to cultivate with activists in and outside of Florida.

Again from Erickson:

Marco Rubio, on the other hand, has been a bold conservative reformer. He has been an unapologetic champion of free people and free markets. While Crist has raised taxes, Rubio has fought to cut taxes and balance budgets… Rubio has fought for the idea that people should be judged not based on their skin color or their family’s background, but on their personal achievements and merit.

Rubio is drawing the battle lines on fiscal issues, staking out the position that he will give Floridians an honest choice between Republican and Democrat philosophies on the economy, and Florida GOP operatives, “believe that Rubio has the potential to be a formidable opponent.”

But they also point to a growing undercurrent of mainstream conservative dissatisfaction, beginning with Crist’s decision to appear at a February rally alongside Obama to raise support for the stimulus. Over the past several months, The Wall Street Journal editorial page has railed against Crist over his plans to control property insurance premiums and his support for higher government spending.

“Crist doesn’t represent a right-wing philosophy or a left-wing philosophy. He represents no philosophy,” said Ana Navarro, a leading GOP fundraiser in Florida who has been one of Crist’s most outspoken Republican critics.

“A lot of Republicans are intrigued by the notion of an articulate, conservative young Hispanic that brings things to the table that the national party so badly needs right now. But the big question is going to be the money. Being governor provides a platform for raising money that’s tough to match.”

This brings us back to the broader discussion of how the Republican party wants to move forward. In the wake of the Specter switch, and the trouncing at the GOP suffered at the voting booth last November, many are asking where this party needs to go to grow its appeal and regain a majority in Congress. Crist is an unabashed moderate, and Rubio a committed conservative. With the swift backing of national party leaders behind Crist, it seems that Washington Republicans want their party to move to the center.

No one who knows Crist thinks he will run — either for the Senate or for president in 2012 — as anything but a new sort of establishment Republican; former Arkansas governor Mike Huckabee or Alaska Gov. Sarah Palin he is not. Should Crist get elected next November, he will immediately surge to the top (or close to it) of the group of moderate Republicans calling for a change in the way the party defines itself.

Rubio is already out with a commercial pointing out the “Obama Republican” label that Crist earned by supporting the Presidents bailout package which was wildly unpopular among the GOP base.

In Pennsylvania, Florida, Texas and other states across the country next year, Republicans will go to the polls to determine which direction they want their party to grow. A vote for Crist is a decidedly moderate vote for less fiscal restraint, a policy which many blame for Republican losses in recent elections. A vote for Rubio places Republican squarely in the camp of fiscal responsibility and smaller government principals. Thankfully, the GOP will be able to settle this debate through primaries. As NRSC Chairman John Cornyn said recently, “I tend to think primaries are not all bad.” Conservatives in Florida, Pennsylvania and elsewhere undoubtedly agree.