A new ABC/Washington Post poll shows a record 58 percent of registered voters nationwide now support marriage equality.
The poll also shows that 64 percent of U.S. voters think the U.S. Constitution should be the basis for deciding whether same-sex couples can marry.
The poll released on March 18 also showed increasing support for marriage equality among many demographic groups:
• Adults 18-29 support marriage equality at 81 percent.
• Support among seniors has climbed 26 percentage points in nine years to 44 percent.
• Support among Republicans has climbed 18 points since 2004 to 34 percent.
• Support among Independents is at 62 percent, up from 38 percent nine years ago.
• Support among Democrats is at 72 percent. In 2004, support among the party's voters was just 29 percent.
• Support among conservatives is at 33 percent, 10 points higher than in 2004.
• Support among Catholics is at 59 percent, up 19 points from 2004.
The poll was released a week ahead of Supreme Court arguments on two marriage-equality cases – one on California's Proposition 8, which amended the state constitution to ban same-sex marriage, and the other on the federal Defense of Marriage Act, which requires the federal government to refuse to recognize same-sex marriages.