By Mark Egan
NEW YORK (Reuters) - Most Americans oppose gay marriage and same-sex unions but nevertheless do not support President Bush's proposal to amend the U.S. Constitution to define marriage as between a man and a woman, a new poll revealed Thursday.
The Quinnipiac University Polling Institute survey found that 63 percent of Americans were against gay marriage while 31 percent favored marriage for same-sex couples.
The poll of 1,865 registered voters nationwide, with a margin of error of 2.3 percentage points, found that older Americans were more likely to be opposed to gay marriage.
Younger voters aged 18 to 34 opposed gay marriage by a margin of 52 percent to 44 percent. Of those 65 or older, 77 percent were opposed compared with 15 percent in favor.
The issue of gay marriage has become a hot-button election year issue ahead of the presidential vote in November after thousands of gay and lesbian couples were married in San Francisco and elsewhere.
Bush has denounced such nuptials as undermining the institution of marriage and has proposed a constitutional amendment that would effectively ban gay marriage.
His Democratic opponent, Sen. John Kerry of Massachusetts, is also against fully-fledged marriage but supports civil unions for gays and lesbians.
The Quinnipiac poll suggested neither position was likely to curry favor with voters in November's election.
American voters opposed amending the U.S. Constitution to ban same-sex marriage by a margin of 51 percent to 41 percent. They also opposed allowing same-sex civil unions 53 percent to 40 percent.
"Americans don't like gay marriage 2-1," said Maurice Carroll, director of the Quinnipiac University Polling Institute. "They also oppose by a smaller margin John Kerry's position in favor of same-sex civil unions.
"But by almost the same margin, they oppose President Bush's call to amend the Constitution to ban gay marriage," Carroll said.
The Hamden, Conn.-based university conducted the poll March 16-22.
The gay marriage issue came to prominence this year when Massachusetts' highest court ruled that gay marriages should be allowed to begin in that state in May. That ruling sent ripples throughout the nation.
About 4,000 gay couples were married in San Francisco in one month before California's Supreme Court ordered the city on March 11 to halt the same-sex marriages.
Gay marriages have also taken place in Oregon, New York, New Jersey and New Mexico, and the issue has prompted a flurry of lawsuits across the nation from gay-rights advocates who believe that barring gay marriage is discrimination.