(WASHINGTON) -- The bandwagon for support of same-sex marriage keeps getting more crowded with the addition of two more high-profile passengers.
On Monday, Virginia Democratic Sen. Mark Warner said on a Facebook posting that endorsing the rights of gay and lesbian couples to marry was "the fair and right thing to do."
According to Warner, who comes up for reelection next year, his new support is "the inevitable extension of my efforts to promote equality and opportunity for everyone."
Meanwhile, Missouri Democratic Sen. Claire McCaskill announced her decision to back homosexual nuptials last Sunday.
McCaskill, who won reelection in November, says her position is based on "a country founded on the principals of liberty and equality."
In her post on Tumblr, the lawmaker admitted, "Good people disagree with me. On the other hand, my children have a hard time understanding why this is even controversial. I think history will agree with my children."
Generally, Democrats have been more partial to endorsing same-sex marriage but more Republicans have been changing their views as well, as the Supreme Court begins hearing arguments Tuesday on the constitutionality of California's Proposition 8 and the 1996 Defense of Marriage Act.
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