This is a partial transcript of The Big Story With John Gibson, May 17, 2004, that has been edited for clarity.

JOHN GIBSON, HOST: Partisan politics over same-sex marriage could play a role in this year's election, especially in big battleground states. Former presidential pollster Pat Caddell (search) is president of Cambridge Survey Research (search). Pat, today's big question, will Democratic support for gay marriage alienate swing voters?

PAT CADDELL, CAMBRIDGE SURVEY RESEARCH: Well, John, that depends on how this issue is raised. But, overwhelmingly, the public in terms of favoring or opposing gay marriage has actually been increasing its opposition. It depends on the polls. It's roughly around 60 percent — it's actually more than 60% against gay marriage. Support for a constitutional amendment, which was originally some months ago out of consensus against it now has a majority for it, although I don't think enough. The real question is what does it do to the politics of the vote?

For the first time the groups that are the greatest opposition looking demographically at the electorate comes from the Democrat's minority base. African-American blacks are 75 — 70% to 75% opposed. They're right behind the Hispanics. In that same category are voters over 65, particularly blue-collar voters over 65. Those are — the Democratic base has never been challenged on a cultural issue they felt strongly about. This is an issue that — that is felt strongly about by these groups, how it plays out. It's not likely to change for republicans. What it's likely to do is create cross-pressures, and we've seen some of the incidents of this already.

There have been two political tests already, interestingly. One was in the Pennsylvania primary. Senator Specter was being challenged by a social conservative, partly on the issue of gay marriage. He was supported by Rick Santorum, who is — Rick Santorum supported Senator Specter. He is very strong on social issues and is from the Pittsburgh area. In southwest Pennsylvania, the area most economically depressed, very blue-collar, Democratic area, but in the primary Toomey was the Republican challenger carried that area with 59% of the vote. He got 55% of the vote in Allegheny County, which is Pittsburgh.

It's the only area he carried outside of his own home county. In Massachusetts, ironically, the Cheryl Jacques who is now the executive director of the Human Rights Campaign, which is a gay-lesbian human rights group nationally, left — resigned from her seat March 2nd during the primary. There was a special election in Massachusetts, and in her very safe Democratic liberal seat, liberal area, a Republican won that seat in the special election for the state senate.

GIBSON: Pat, let's back up just so I got this straight. John Kerry (search) is going out there trying to beat George Bush who has his base relatively secure. John Kerry has to make sure he has his base secure. That is African-American voters and Hispanic voters which in many places in the country are — vote Democrat overwhelmingly. And those you are telling me are the precise groups which overwhelmingly oppose gay marriage. How does Kerry get out of this?

CADDELL: They hope it doesn't become an issue.

GIBSON: Didn't it just become an issue?

CADDELL: I think it has, because I will tell you in San Francisco when we went through that weak period when the mayor of San Francisco decided he was going to marry people, the numbers went down. Not only in terms of support for gay marriage and the support went up for the constitutional amendment, but, more importantly, you have to dig deeper because a the lot of people are very skittish about how they talk about this. But interestingly enough, opposition to the gay lifestyle, if you will, also increased. The tolerance level, which had been much higher went down. You know, last July — by the middle of last year, half the people basically in the country favored civil unions. That's dropped about 10 points now.

GIBSON: Pat, let me ...

CADDELL: Kerry's problem is — let me say, John, Kerry's problem, in part, is that he voted against the Defense of Marriage Act (search). Also, it's his state that is doing this, and he says he is for marriage between a man and woman, but he is not really— he didn't really do very much. That's going to be part of the claim against him. But look at California. Barbara Boxer, our senator here, who is up for re-election this year, from San Francisco, is probably one of the most, if not the most liberal, senator down there. She is adamantly opposed to gay marriage and is running on civil unions in California, which everyone thinks is the most liberal state in the union. You figure that out.

GIBSON: Pat Caddell, Democratic problems over Democratic politics. Pat, it's always good to talk to you. Thanks for coming in. We'll see you again.

CADDELL: OK, thanks.

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