Maggie Gallagher and Andrew Sullivan will debate gay marriage on April 4 in Lexington, Virginia.

Gallagher, the co-founder and former president of the National Organization for Marriage (NOM), the nation's most vociferous opponent of gay marriage, and Sullivan, the former editor of The New Republic and the blogger behind The Dish, will face off starting at 6PM in Lee Chapel on the campus of Washington and Lee University.

The debate is being hosted by Outlaw and the Federalist Society, two Washington and Lee University School of Law student groups.

Under Gallagher's leadership, NOM worked to pass California's gay marriage ban, Proposition 8, and repeal a gay marriage law in Maine.

Most recently, Gallagher's talking points have included calling marriage equality supporters intolerant.

“What they've done now is that they've stopped trying to persuade people that gay marriage is a good idea,” she said at an event organized by the socially conservative group Sutherland Institute. “What they are doing is raising the cost of speaking out … by directing a relentless torrent of accusations and hatred against anyone who speaks, no matter how civilly, for marriage.”

Sullivan, who is openly gay, will present the conservative case for gay marriage.