The four Republicans campaigning for Senate in Virginia will meet for their second debate Friday night, as time is running out for George Allen’s foes to stall his momentum.

Del. Bob Marshall (R), second from right, talks during the first of three debates in Roanoake, Va. Other GOP candidates participating in the debate are, from left, former Virginia senator George Allen, Chesapeake minister E.W. Jackson and former tea party leader Jamie Radtke. (Stephanie Klein-Davis/The Roanoke Times via AP)

With the June 12 primary a month away, Allen continues to cement his front-runner status, making him the most likely Republican to face former governor Timothy M. Kaine (D) in November for the seat of retiring Sen. James Webb (D).

The American Conservative Union and National Rifle Association endorsed Allen on consecutive days this week, giving him key support on the right as his three opponents try to make the case that he is insufficiently conservative. Those endorsements followed the release of a Washington Post poll showing Allen getting 62 percent of the vote among likely GOP primary voters. Marshall was next with 12 percent, while Radtke and Jackson earned 5 and 3 percent, respectively.

At the first primary debate, held April 28 in Roanoke, Radtke, Marshall and Jackson tried to varying degrees to focus their fire on Allen. Radtke, in particular, leveled criticism of Allen’s record on spending issues during his previous term as senator, lumping him in with “career politicians in both parties.”

Marshall touted his own record in the state House, both on spending issues and on jousting with Kaine when the Democrat served as governor. Jackson, for his part, got some positive reactions from the crowd with his quick wit and for saying, “I am not an African American, I am an American.”

As he has throughout the primary, Allen kept his attention on Kaine, essentially running a general election campaign and largely declining to engage with his Republican opponents.

That debate covered a wide range of topics, from the economy and jobs to student loans and the Supreme Court. Friday’s gathering could also include questions about gay marriage, given President Obama’s announcement this week that he believes the practice should be legal.

The debate is also likely to include questions of interest to the Virginia business community, as the moderator will be Nicole Riley, state director of the National Federation of Independent Business. The three panelists will be Virginia business owners: Tim Ciampaglio of the Pharos Group Inc., Betsy Atkinson of ERA Atkinson Realty and David Creecy of Poquoson Pharmacy.

The third debate will be May 25 in Falls Church.