Democrats proposed codifying the right for same-sex couples to marry into federal law in response to Supreme Court Justice Clarence Thomas suggesting that same-sex marriage should be legalized nationwide.
47 Republicans joined all House Democrats in voting in favor of the legislation.
Some hard-right Republicans, including the Freedom Caucus chairman, voted for the bill.
The 1996 Defense of Marriage Act defined marriage as only a legal union between one man and one woman and was signed into law by former President Bill Clinton.
Federal law would be changed to include interracial marriage.
It's not clear if the bill will have the support of at least 10 Republican senators, the amount needed to overcome the filibuster. McConnell hasn't said how he'll vote.
Thomas' opinion was attached to the Supreme Court ruling that ended the right to abortion. Justice Samuel Alito stated in the majority opinion that Thomas' view was not that of the court, and argued that Obergefell is an entirely different issue from the case of abortion.
Wade Overturned is the ultimate explanation of what it means.
Clarence Thomas thinks the court should reconsider gay marriage and birth control decisions.