The Washington Post reports:
A full 50 percent say gay marriage is protected by the Constitution’s Equal Protection clause, an argument repeated by judge after judge in a string of federal rulings against state bans since a pivotal Supreme Court decision last summer. Some 43 percent do not believe gay marriage enjoys constitutional protection. Support for gay marriage overall — regardless of views on whether it is constitutionally protected — enjoys broader support, with 56 percent saying they back the right for same-sex couples to marry and 38 percent opposing it.
When asked if they support marriage equality more generally, support climbs to 56%.