Politically active Christians, among others, say marriage is the next great social issue for the church in North America. "I think we're on the front side of another Roe v. Wade," Bill Murray, spokesman for the Family Research Council, told Christianity Today. "It's definitely going to be the biggest issue during the election."

Leaders say the issue transcends political ideology.

"Every once in a while, a great nation has to deal with a great issue," American Values president Gary Bauer said at an October press conference in Washington, where 24 founding members of the Coalition to Protect Marriage made their case. "Millions of people understand that it's not bigotry to believe that marriage is between a man and a woman."

Spurred by pro-gay court rulings in Canada, the U.S. Supreme Court's Lawrence and Garner v. Texas decision, and last week's Massachusetts' Supreme Court ruling, the coalition is using radio and television broadcasts, daily e-mails, and two websites (MarriageProtectionWeek.com and nogaymarriage.com) to urge citizens to contact their elected representatives.

On another website (protectmarriage.org), the Family Research Council has included a sample sermon and talking points. FRC also is distributing a Marriage Protection Pledge it will ask all federal and state elected officials to sign.

"Americans cannot defend politicians who will not defend marriage," said Sandy Rios, president of Concerned Women for America.

Marriage defenders already have one high-profile ally: George W. Bush. The President declared October 12-18 as Marriage Protection Week. In his proclamation, Bush said, "Marriage is a union between a man and a woman."

In reaction, Democratic National Committee Chairman Terry McAuliffe said, "In a desperate ...