Maine residents have approved same-sex marriage, giving the gay rights movement a breakthrough victory.

Gay marriage is legal in six states and Washington, D.C., but those laws were either enacted by lawmakers or through court rulings. In popular votes, more than 30 states had previously held elections on same-sex marriage, with all losing.

Maine, Maryland and Washington state were holding up-or-down votes Tuesday on legalizing gay marriage. Minnesota was voting on a proposal to ban gay marriage in the state constitution.