White House lawyers are studying how to keep legal marriage strictly between a man and a woman. The Senate plans hearings on how to stop gay marriage. And a constitutional amendment to ban gay marriage increasingly is picking up support.

For those fighting to protect traditional marriage, amending the Constitution is the only way to stop federal judges or state courts from one day, probably soon, allowing gay couples to marry.

"Within the last couple millennia ... no human civilization has ever defined marriage as anything other than the coming together of men and women," said Glenn Stanton, senior analyst for Focus on the Family, a Christian ministry in Colorado. "It really matters for a culture how we define marriage." ...