The effort to repeal the constitutional definition of marriage gained its first Republican supporter on Friday.

Rep. Ileana Ros-Lehtinen (R-Fla.) announced she will co-sponsor the legislation to repeal the federal Defense of Marriage Act (DOMA). 

“I voted against the constitutional amendment defining marriage [in 2006] so I’m pleased to co-sponsor the repeal of DOMA and work with my colleagues on marriage equality,” Ros-Lehtinen told The Advocate.

Ros-Lehtinen, the chairwoman of the House Foreign Affairs Committee, has been an advocate of gay and lesbian rights. She pushed for the recent repeal of the "Don't ask, don't tell" policy that prevented gay and lesbian Americans from serving openly in the U.S. military. Log Cabin Republicans, a Republican organization that represents gay and lesbian Americans, thanked Ros-Lehtinen for signing onto the bill.

“It is time that our law respected all marriages. There is much work to be done to make that dream a reality, but with Congresswoman Ros-Lehtinen’s leadership, marriage equality is on the horizon,” Executive Director R. Clarke Cooper said in a statement.

House Republicans have pledged to protect DOMA despite the Obama administration’s announcement earlier this year that the attorney general would no longer defend challenges to the amendment in court. Ros-Lehtinen’s break with Republican leadership is a significant gain for Democrats who want to repeal the amendment, since legislation to repeal now has bipartisan support.

“I co-sponsored the repeal of DOMA because I firmly believe that equality is enshrined in our Constitution and in our great democracy," Ros-Lehtinen said in a statement released by Log Cabin Republicans.