Former Gov. Jim Gilmore appears to have an early lead over Del. Robert G. Marshall of Prince William to be the Republican nominee for the U.S. Senate.

Republican leaders say the long-standing party ties of Gilmore, Virginia's governor from 1998 to 2002, have attracted a majority of the delegates chosen so far, about three-quarters through the delegate selection process.

"I feel pretty confident that particularly in the Richmond area there is a lot of support for Jim Gilmore," said Linwood Cobb of Henrico County, the 7th District Republican chairman.

But Cobb cautioned that a lot of delegates remain to be chosen in the district, including delegates from Henrico.

Republicans will choose their nominee May 31 at a convention at the Greater Richmond Convention Center. The winner will take on former Gov. Mark R. Warner, a Democrat, in the general election Nov. 4.

Almost 75 percent of the delegates have been selected. Marshall, with the type of activist followers who tend to show up at conventions, is still in a position to win, political commentator Steve Farnsworth said.

"It's very much a turnout contest," the University of Mary Washington political scientist said.

During his 16 years representing Prince William and Loudoun counties in the House of Delegates, Marshall has been most strongly associated with the anti-abortion movement.

Robert Stuber, the Spotsylvania County GOP chairman, said the delegates who filed at the county's mass meeting April 5 appeared to be split 50-50 between Marshall and Gilmore. But those who paid a voluntary filing fee of $35 and are most likely to show up at the convention appeared to be party regulars who tend to back Gilmore, he said.

Steve Waters, campaign manager for Marshall, disputed this. Marshall won a 3-to-1 majority in Spotsylvania, he said.

David Avila, GOP chairman of the inside-the-Beltway 8th Congressional District, said "I didn't see a whole lot of new folks who filed" in the district. "The traditional folks are those who either like Gilmore or don't like Bob Marshall very much," he added.

"Things are going great," Gilmore said in a telephone interview. "We are happy with where we are."

Although more cautious than Gilmore, Marshall said "if this trend continues, we feel good about the contest."

A third candidate, Robert D. "Bob" Berry of Springfield, entered the race late without prior elected experience.

"I am winning some support," said Berry, a civilian contractor who spent 25 years in the Navy Reserves.

As he makes the rounds of mass meetings, Gilmore has been citing his experience.

"I have been attorney general, governor and national chairman of the Republican Party," he said. "I have the best chance of beating Mark Warner."

Gilmore said he is getting support from some of his 3,500 appointees while he was governor, but he said party regulars also are backing him. Many of the former appointees have signed on as delegates.

As a sign of his optimism, Gilmore has been traveling out of state raising money for an expected expensive battle with Warner. He was in Texas and New York last week.

"We are not taking the race for granted, it's reality," said Dick Leggitt, Gilmore's longtime associate and campaign manager. "If we wait until June, we can't beat Warner," he added, referring to Warner's deep pockets. A self-made investor, Warner is said to be worth about $200 million.

"Gilmore is trying to build up a sense of inevitability to try to discourage Marshall backers from going to the convention," Waters said.

Marshall also is focusing on Warner.

"We helped beat Mark Warner on the marriage amendment, despite being outspent by a large amount," he said, referring to the 2006 amendment to the Virginia Constitution that banned same-sex marriage. Warner opposed the amendment.

Marshall also is touting his successful court challenge to the Northern Virginia Transportation Authority. The Virginia Supreme Court ruled Feb. 29 that the authority was unconstitutional, because it allowed non-elected officials to impose taxes.

As homeowners in Northern Virginia, Warner and Gilmore could have brought suit, just as he did, Marshall said. Gilmore points out that he lowered taxes when he was governor.

Marshall has been critical of Gilmore's stance in support of a woman's right to choose during the first two months of pregnancy.

Anti-abortion Republicans are likely to constitute a big part of Marshall's delegation. But Gilmore consultant M. Boyd Marcus Jr. of Richmond said the campaign has picked off a number of the delegates because of anti-abortion actions Gilmore took when he was governor.

Berry says his "uncompromising adherence to the conservative world view" and his experience on national security and intelligence issues set him apart from the other candidates.

Delegates are being selected at a series of local mass meetings and caucuses held in about 130 localities around the state that began in late February and will end early next month.

Under the state GOP's formula, there are a total of 10,519 delegate votes and a candidate needs 5,260 to capture the nomination.

Contact Tyler Whitley at (804) 649-6780 or twhitley@timesdispatch.com.