Republicans have historically opposed same-sex marriage, while being divided on civil unions and domestic partnerships. During the 2004 election, George W. Bush campaigned prominently on a constitutional amendment to prohibit same-sex marriage; many believe it helped George W. Bush win re-election in 2004. In both 2004 and 2006, President Bush, Senate Majority Leader Bill Frist, and House Majority Leader John Boehner promoted the Federal Marriage Amendment, a proposed constitutional amendment which would legally restrict the definition of marriage to heterosexual couples. In both attempts, the amendment failed to secure enough votes to invoke cloture and thus ultimately was never passed. As more states legalized same-sex marriage in the 2010s, Republicans increasingly supported allowing each state to decide its own marriage policy. As of 2014, most state GOP platforms expressed opposition to same-sex marriage. The 2016 GOP Platform defined marriage as "natural marriage, the union of one man and one woman," and condemned the Supreme Court's ruling legalizing same-sex marriages. The 2020 platform retained the 2016 language against same-sex marriage.