Stunned and angry, national gay rights leaders Wednesday blamed scare-mongering ads - and President Barack Obama's lack of engagement - for a bitter election setback in Maine that could alter the dynamics for both sides in the gay-marriage debate.

Conservatives, in contrast, celebrated Maine voters' rejection of a law that would have allowed gay couples to wed, depicting it as a warning shot that should deter politicians in other states from pushing for same-sex marriage.

"Every time the citizens have voted on marriage, they have always sided with natural marriage," said Mathew Staver, founder of Liberty Counsel, a Florida-based Christian legal group. "Maine dramatically illustrates the will of the people, and politicians should wake up and listen."

Gay activists were frustrated that Obama, who insists he staunchly supports their overall civil rights agenda, didn't speak out forcefully in defense of Maine's marriage law before Tuesday's referendum. The law was repealed in a vote of 53 percent to 47 percent.

"President Obama missed an opportunity to state his position against these discriminatory attacks with the clarity and moral imperative that would have helped in this close fight," said Evan Wolfson of the national advocacy group Freedom to Marry. "The anti-gay forces are throwing millions of dollars into various unsubtle ads aimed at scaring people, so subtle statements from the White House are not enough."

Marriage debate simmers
The White House, asked about the criticism, had no immediate comment.