02/27/2004 - Gay marriage has surpassed other major social issues like abortion and gun control in its influence on voters. Four-in-ten voters say they would not vote for a candidate who disagrees with them on gay marriage, even if they agree with the candidate on most other issues. By comparison, 34% say they would not support a candidate who disagrees with them on abortion and 32% expressed that opinion about a candidate's stance on gun control.

Yet while gay marriage has a greater overall impact on voters than either abortion or gun control, the nature of its influence is quite different. For the most part, gay marriage is a make-or-break voting issue only to the opponents of that idea; supporters of gay marriage generally say a candidate's stance would not affect their vote. Moreover, even among gay marriage opponents, the issue has a disproportionate impact on some groups ­ notably conservative Republicans, evangelical Christians and voters age 65 and older.

The latest Pew Research Center national survey shows that voters oppose gay marriage by more than two-to-one (65%-28%), a margin that has remained generally steady since October. (This survey was conducted Feb. 11-16, prior to President Bush's Feb. 24 announcement that he would support a constitutional amendment to ban gay marriage). (This analysis based on registered voters only; topline based on general public.)

Other recent national surveys have found that, in spite of the broad opposition to gay marriage, the public is divided over a constitutional amendment to ban the practice. An ABC News/Washington Post poll conducted Feb. 18-22 showed that 46% support a constitutional amendment while 45% believe it should be up to each state to make its own laws regarding homosexual marriage.