(CNN) – A second Democratic senator came out in support of same-sex marriage Monday as high-profile politicians continue to make their views known ahead of this week's Supreme Court arguments.
Sen. Mark Warner, D-Virginia, wrote on his Facebook page, "I support marriage equality because it is the fair and right thing to do. Like many Virginians and Americans, my views on gay marriage have evolved, and this is the inevitable extension of my efforts to promote equality and opportunity for everyone."
Earlier in the day, Democratic Sen. Claire McCaskill of Missouri similarly endorsed same-sex marriage, saying she had "come to the conclusion that our government should not limit the right to marry based on who you love." Both Virginia and Missouri have large swaths of conservative voters.
In his statement, Warner noted that as governor, he passed laws protecting gay and lesbian state employees under anti-discrimination measures. He also supported ending the military's "don't ask, don't tell" policy.
"I believe we should continue working to expand equal rights and opportunities for all Americans," he wrote.
Earlier this month, Sen. Rob Portman became the first Republican in the Senate to back same-sex marriage, explaining his decision was influenced by his son, who is gay.
The Supreme Court will hear arguments Tuesday and Wednesday relating to the legality of same-sex marriage, which decisions expected in June.