Montana senator Jon Tester announced on Facebook Tuesday that he would support gay and lesbian couples' right to marry.
Tester, a Democrat, also changed his official Facebook page's profile photo to the popular red equality sign that many are displaying this week in light of the Supreme Court's hearing on marriage equality.
"Montanans believe in the right to make a good life for their families," he said in a Facebook post Tuesday afternoon, hours after the Proposition 8 hearing ended. "How they define a family should be their business and their business alone. I'm proud to support marriage equality because no one should be able to tell a Montanan or any American who they can love and who they can marry."
Tester is the latest in a string of Democratic senators to come out in favor of marriage equality as the Supreme Court takes up the issue, including Claire McCaskill of Missouri, Mark Warner of Virginia, and Mark Begich of Alaska.
Montana's senior senator, Democrat Max Baucus, expressed his support for marriage equality last year after the state's party backed same-sex marriage rights it in its platform.