Former Housing and Urban Development Secretary Mel Martinez (R) will kick off his Florida Senate campaign in Washington, D.C., tonight, aided by the chamber’s top GOP leaders — who had little to say Monday about what appears to be their collective decision to back his candidacy.

Six of the Senate’s top leaders — Majority Leader Bill Frist (Tenn.), Majority Whip Mitch McConnell (Ky.), GOP Conference Chairman Rick Santorum (Pa.), Conference Vice Chairman Kay Bailey Hutchison (Texas), GOP Policy Committee Chairman Jon Kyl (Ariz.) and Appropriations Chairman Ted Stevens (Alaska) — are listed as honorary co-chairmen of the fundraiser.

National Republican Senatorial Committee Chairman George Allen (Va.), who was criticized last year for lending his name for candidates’ fundraisers in competitive GOP primaries, is conspicuously missing from the invitation. But the event is being held at the Ronald Reagan Republican Center, the building that houses the NRSC.

“Clearly Mel Martinez is the frontrunner. Clearly he has the name ID, and clearly he has the connections here in Washington to win this race,” said a senior GOP leadership aide, speaking on the condition of anonymity.

Meanwhile, spokesmen for the top three Senate leaders offered no comment when asked whether their bosses’ participation in the $1,000 a ticket event should be viewed as an endorsement of Martinez.

The former HUD secretary, who left his job in the Bush administration late last year in order to run, is one of a half dozen Republicans seeking the seat of retiring Sen. Bob Graham (D). Among the other leading GOP candidates are state House Speaker Johnnie Byrd, former Rep. Bill McCollum and state Sen. Daniel Webster. Still, Martinez is widely viewed as the White House-backed candidate in the race.

Campaign spokesmen for two of Martinez’s opponents said their candidates were busy raising money in the state and were not concerned about D.C. fundraisers.

“We’re focusing on Florida,” said McCollum spokeswoman Shannon Gravitte. “We feel confident about our position and that Bill McCollum will be our next Senator from Florida.”

NRSC spokesman Dan Allen said Senator Allen may stop by the event and also stressed that “any of the other Florida candidates can ask” to use the NRSC facilities for a fundraiser. “A lot of campaigns will ask us to use the building when they’re doing events in Washington,” Allen said.

In addition to the chamber’s top leaders, the invitation reads like a Who’s Who of GOP lobbyists and political luminaries.

Among the co-chairmen of the event are lobbyist Jack Abramoff, Scott Reed, who managed then-Sen. Bob Dole’s (R-Kan.) 1996 presidential bid, and Mitch Bainwol, a former chief of staff to ex-Sen. Connie Mack (R-Fla.) and one-time executive director of the NRSC, who is now chief executive of the Recording Industry Association of America. Mack is chairing McCollum’s campaign.

Hosts include Kirk Blalock, a partner with Fierce, Isakowitz and Blalock who served two years as head of business outreach in the Bush White House, and T.J. Petrizzo, a former chief of staff to Rep. Jennifer Dunn (R-Wash.).