"Advisers to former governor James S. Gilmore III claim that he has essentially locked up the GOP nomination for U.S. Senate, but his chief opponent says Gilmore is bluffing because he is on the verge of an embarrassing loss at the state convention next month.

In a campaign directed at a few thousand GOP activists who choose the nominee, Gilmore has been locked in a surprisingly intense struggle with Del. Robert G. Marshall (Prince William). Robert D. "Bob" Berry of Springfield is also running, but Marshall has posed the biggest threat to Gilmore, who earlier this year was not expecting a challenger.

The Virginia GOP convention is not until the last weekend in May, but the convoluted process for selecting the nominee to run against former governor Mark R. Warner (D) has been underway since last month, when Republican county and city committees started meeting to select delegates to the state convention.

Gilmore and Marshall have dispatched paid staff and surrogates across the state to try to persuade supporters to attend the meetings and register as delegates. About half of the local meetings have taken place, with new ones almost daily until April 26.

Marshall, a fierce opponent of abortion and tax increases, is said to be running strong among Northern Virginia delegates elected so far.

But based on early returns from the county meetings, Gilmore strategist M. Boyd Marcus said "there really isn't any doubt" that Gilmore will be the nominee because he is winning big in many rural counties as well as suburban Richmond and Hampton Roads.

Gilmore, a former attorney general and prosecutor, is relying on a network of supporters he built during his previous two bids for statewide office. Marshall is mounting his first statewide campaign.

"They really don't have anyone on their side that has really done this before," Marcus said of Marshall's campaign. "They never really understood what was happening around them. You can't build support on a statewide basis in a month or two."

Marshall counters that Marcus is trying to deceive people into thinking Gilmore has the race won to depress turnout at the remaining local meetings.

"From what we can tell, we are ahead," Marshall said. "This is someone who is bluffing at poker because he doesn't have a good hand."

Marshall estimated that he has secured three of every four delegates in Loudoun County as well as a majority in Fairfax County, where activists had until late March to register as delegates. Marshall also expects to rack up big margins in Prince William County, where activists will convene today to choose delegates.

Marshall said he has also snared about half of the delegates in heavily Republican Chesterfield County in suburban Richmond. If true, the Chesterfield results could be a bad sign for Gilmore, who lives in suburban Richmond.

But both campaigns are essentially guessing at their level of support. Many of the local GOP committees have not released final delegate lists, meaning the campaigns are making assumptions based on whom they saw at the local meetings.

Adding to the uncertainty, some delegates may be able to cast as many as 25 separate votes for the same candidate while others get just fractions of a vote. The discrepancy arises because each county and city is given a certain number of votes -- based on the performance of recent Republican candidates in those areas -- regardless of how many people sign up to be delegates.

"Anyone who tells you they have a vote count right now is fooling you," said GOP strategist J. Kenneth Klinge, a Marshall supporter from Northern Virginia.

Candidates also have to make sure the delegates, who can change their mind about who they want to support, show up at the convention in Richmond.

Patrick M. McSweeney, a former chairman of the Virginia Republican Party, said the campaign will continue right up to the convention.

"There will probably be negative charges that have to be responded to and there will be disinformation campaigns and some persuasion involved," McSweeney said. "But most of the effort is turnout."

Because there is no way to determine the outcome, there are often upsets at conventions. Social conservatives have also tended to dominate conventions.

In 1993, Michael P. Farris surprised many in the party by defeating Bobbie G. Kilberg for the nomination for lieutenant governor. Farris, a home-schooling advocate who lost the general election to Donald S. Beyer Jr., relied on a network of families that home school their children and abortion opponents.

Marshall, who also home-schooled his five children, is employing a similar strategy against Gilmore. Marshall has been critical of Gilmore over his support for abortion rights until the eighth week of a pregnancy. Marshall was also the co-sponsor of a constitutional amendment, which voters approved in 2006, to ban gay marriage and civil unions.

"We are working from the grass roots up," said Steve Waters, Marshall's campaign manager. "A lot of our people are working beneath Gilmore's radar."

Gilmore supporters said he also has deep roots in the conservative movement. Even though he makes no apologies for more moderate views on abortion, Gilmore said he fought for parental notification for minors seeking an abortion and helped enact legislation to ban late-term abortions.

"There is an awful lot of pro-life leaders in the state of Virginia who look at Jim Gilmore's record and say he accomplished a lot of things to help the pro-life cause so they are very comfortable with Gilmore," Marcus said.

Tucker Watkins, a party leader in southern Virginia who has attended nearly a dozen local meetings over the past month, said Gilmore appears to have a slight advantage in that part of the state because he is better organized.

"Marshall has got some good people, but I don't think he has the depth of organization on the paid side," Watkins said. "When you try to deal with all these little meetings all over Virginia at one time, it's a huge task."

Marshall alleges that Gilmore's political organization is starting to play rough. He said some party leaders in Hampton Roads, where Marcus said Gilmore is getting near universal support, are declining to cooperate with his efforts to obtain information about meeting dates and filing deadlines.

"We are experiencing some difficulty with a lack of civility," Marshall said.

But Marshall may be benefiting from personal hostility that some GOP activists feel toward Gilmore, whom they accuse of being dismissive of them when he was governor.

"I have told Bob, 'All you have to do is get all the people who don't like Jim Gilmore to come to the convention and you would beat him 10 to 1,' " Klinge said.

Marshall also stands to broaden his base of support by reaching out to supporters of Rep. Tom Davis (R-Va). Davis, a moderate, spent years preparing to run for the Senate, but abandoned those plans when he was unable to get the state party to hold a primary instead of a convention.

But James E. Hyland, chairman of the Fairfax County Republican Committee, said he has "not seen a big wave" of Davis loyalists coming out for Marshall.

"There are supporters of his who have signed up, but I think it is more to support the party than to try to influence the convention," he said. Hyland added: "I've got to assume [Gilmore] is ahead of the game, but Bob Marshall is doing everything he can."" (Tim Craig, The Washington Post, April 12, 2008)