Sen. Mark Kirk (R-Ill.) announced his support for same-sex marriage on Tuesday, becoming the second sitting GOP senator to do so.
"Our time on this earth is limited, I know that better than most," continued Kirk, who returned to the Senate earlier this year after a lengthy absence to recover from a stroke. "Life comes down to who you love and who loves you back — government has no place in the middle."
Kirk's statement came the same morning that Sen. Tom Carper (D-Del.) also announced that he supports same-sex marriage.
The Human Rights Campaign, a pro-same-sex marriage group, praised the announcements by both Kirk and Carper.
"Sen. Kirk and Sen. Carper have shown tremendous leadership in announcing their support for marriage equality," Human Rights Campaign President Chad Griffin said. "It is a sign of our progress that so many of their colleagues are showing the same political will. Democrat or Republican, there can simply be no excuse for standing on the wrong side of history when it comes to this basic question of justice."
Kirk joins Sen. Rob Portman (R-Ohio), who switched positions in March, as the only sitting Republican senators to support gay marriage.
Last week, the Supreme Court held hearings on challenges to California's Proposition 8, which bans same-sex marriage and the federal Defense of Marriage Act (DOMA), which defines marriage as a union between a man and a woman. The legal challenges brought a flood of high-profile Democratic senators, including many from swing states or traditionally GOP strongholds, publicly supporting gay marriage.
Besides Carper, seven other Senate Democrats have endorsed same-sex marriage in recent weeks: Sens. Jay Rockefeller (W.Va.), Mark Warner (Va.), Bob Casey Jr. (Pa.), Kay Hagan (N.C.), Claire McCaskill (Mo.), Mark Begich (Alaska), and Jon Tester (Mont.).
Polls also show growing acceptance among the public of gay marriage, leading many in the GOP to adopt a softer stance.
Sen. Lisa Murkowski (R-Alaska) last week said her position on the issue was "evolving." Fellow Republican Sen. Jeff Flake (Ariz.) said that while he supported traditional marriage, he believed it "inevitable" that a 2016 GOP presidential contender could openly support gay marriage.
Updarted at 4:38 p.m.