At least one challenger appears to have emerged in what may be a crowded field in the GOP’s quest to unseat Democratic Florida Sen. Bill Nelson.

The Orlando Sentinel reports that state Senate President Mike Haridopolos visited Washington on Monday and Tuesday “for a short trip aimed at raising his profile — and potentially some bucks.”

Haridopolos appeared at a Tuesday event to push a proposal — fueled at least partially by opposition to President Barack Obama’s health care overhaul — that would amend the U.S. Constitution to allow states to repeal the federal law if two-thirds of their state legislatures agree.

“I’d bet that we’d be in the race,” Haridopolos told the Sentinel of the 2012 Senate contest. “We’re talking to folks not just across Florida but across the country about that prospect.”

As Roll Call reported earlier in the month, Haridopolos has been among the likely Nelson challengers, along with Republican Sen. George LeMieux, appointed to fill the remainder of Sen. Mel Martinez’s term and set to leave the chamber in January. LeMieux is still largely expected to run, a decision that would set up a GOP primary with Haridopolos.

Other names in the mix include Republican Reps. Connie Mack IV, Vern Buchanan and Tom Rooney, and state House Majority Leader Adam Hasner.

Roll Call Politics rates this race as a Tossup.

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