While 56 percent of respondents to the Washington Post-ABC poll said they support the decision that DOMA is not constitutional, 41 percent disagreed.
Just over half, 51 percent, agreed with the court ruling on California's Proposition 8, while 45 percent disagreed. The justices found that those challenging a lower-court decision invalidating the proposition defining marriage as between a man and a woman did not have standing to do so.
Only one-third, 33 percent, agreed with the court decision that threw out a provision in the Voting Rights Act requiring states with a history of racial discrimination to get pre-clearance from the Justice Department for changes in election law. Just over half, 51 percent, disagreed.
Democrats and independents were much more likely to support the court's DOMA decision than Republicans. Young people were also more supportive, with a majority of those over 65 disagreeing with the decision.
The poll surveyed 1,005 adults by telephone between June 26 and last Sunday. The margin of error is 3.5 percentage points.