RICHMOND, FEB. 26 -- A Republican finally came forward today to challenge Democrat Charles S. Robb for the U.S. Senate seat being vacated by Republican freshman Sen. Paul S. Trible Jr.

"I have no illusions about the challenge," said Gil Faulk, 44, a political novice who lives in McLean.

Republicans have been without a candidate since Trible surprised and angered many in his party last fall by announcing, after already having raised nearly $2 million, that he would not seek a second term. Trible cited disappointment with the Senate and a desire to spend more time with his family, but many observers said Trible wanted to avoid a showdown with Robb, even though the former Virginia governor had not yet announced his candidacy.

Faulk wasted little time in attacking his would-be November opponent. At a news conference at the state capitol announcing his candidacy, Faulk said a fund-raiser for Robb at the Tysons Corner Sheraton last month "reminded me more of a coronation ball in Vienna, Austria, than a political meeting in Vienna, Va."

The $4,000-a-couple event "symbolizes three problems with the Robb candidacy: a touch of arrogance, excessive money and, most significantly, a lack of substantive discussion of the issues," Faulk said.

Faulk said he will "not be able to compete" with Robb in raising money, but is prepared to put up at least $50,000 of his own money, and hopes to raise between $750,000 and $1 million. He predicted he would "pull off the biggest upset in Virginia's history."

Faulk, who grew up in Richmond and graduated from law school at Washington and Lee University, was vice president and legal counsel to Dow Jones' Wall Street Journal, where he worked from 1968 to 1985. He moved to McLean last May and opened a law office there after buying Words by Wire, a small news service.

Still weighing a race for the GOP nomination is Andrew F. Wahlquist, a McLean consultant and former administrative aide to the state's senior senator, Republican John Warner. Wolquist said today he is "inclined to get in" and will make a decision by next Friday.

Robb is expected to be unopposed for the Democratic nomination. Both parties will choose their nominees at conventions this summer.