Former Republican National Committee chairman Ed Gillespie has pledged to head a national finance committee for Maryland Lt. Gov. Michael S. Steele should Steele enter the 2006 race for U.S. Senate, several sources said yesterday.

The tentative agreement between Gillespie and Steele was struck in May, even before Steele had announced forming an exploratory committee. It has since been conditioned upon Gillespie not getting bogged down as President Bush's point man on the Supreme Court nomination of Judge John G. Roberts Jr., according to three sources close to the exploratory committee, who spoke on condition of anonymity because the deal is not final.

Should Gillespie assume the pivotal volunteer role, it would reinforce the heavyweight backing Steele would have in seeking to capture a Senate seat that Democrats have held for nearly four decades.

On Tuesday night, presidential aide Karl Rove headlined Steele's first fundraiser for his exploratory committee. The event brought in $75,000.

Political analysts said that, especially this early on, access to the kind of national donor provided by the likes of Rove and Gillespie could strengthen a Steele bid in a state where Democrats hold a nearly 2 to 1 advantage among registered voters. But the national backing has its drawbacks as well.

"It is more proof that Michael Steele is going to do the bidding for the right-wing agenda of the national Republican Party," said Terry Lierman, chairman of the Maryland Democratic Party. "What we're going to see is a Republican attempt to buy the state of Maryland. Maryland Democrats are not going to let that happen."

The Senate seat, up in November 2006, is being vacated by Paul S. Sarbanes. Three Democrats have announced intentions for Sarbanes's seat: Rep. Benjamin L. Cardin, former congressman and former NAACP leader Kweisi Mfume and Baltimore activist A. Robert Kaufman.

Gillespie, a Washington communications specialist, chaired the Republican Party during the 2004 campaign and spent more than a decade as a top aide to former House Majority leader Richard K. Armey (R-Tex.). He did not return calls to his office yesterday.

Staff writer Dan Balz contributed to this report.

Sources say the RNC's Ed Gillespie has offered to direct national fundraising for a Steele Senate bid.Lt. Gov. Michael Steele raised $75,000 at his first fundraiser for his exploratory committee.