Not a surprise, but yet to be confirmed by other less..Fox-y sources:

Republican Florida Governor Charlie Crist has decided he will run as an independent in the race to fill the Florida U.S. Senate seat, Crist allies tell Fox News. The official announcement is scheduled for Thursday at 5pm ET in St. Petersburg, Florida.

The Senate campaign has been rough and tumble for Crist, he was once the front-runner -- but in recent months began trailing his GOP opponent, Florida State Speaker Marco Rubio.

Crist has said that under no circumstance would he drop out of the race, saying he will do what is best for the voters of Florida. The governor says Republicans in Washington want him to stay in the Republican party but voters in Florida have told him they want him to run as an independent.

His campaign and the governor's office have not officially confirmed anything, however this move by Crist has made internal communications difficult because some staff are unlikely to continue to work with Crist as an independent candidate.

The governor is expected to use much of Thursday for courtesy calls to supporters, allies and some Republican officials nationwide. Close advisers expect him to say tomorrow that he looks forward to caucusing with Republicans but that is not a certainty, there are still some issues being worked out and discussed.

Rubio has clinched endorsements from big name Republicans including former Vice President Dick Cheney, New York Mayor Rudy Giuliani and former 2008 presidential candidate and Massachusetts Governor Mitt Romney.