Catholic League President Bill Donohue has suggested President Barack Obama will next evolve to support polygamy.

Reacting to the news that Obama had just become the first sitting president to endorse gay marriage, Donohue said Obama had “fully broken with his Christian moorings.”

“The President of the United States likes the idea of Tom and Dick marrying,” Donohue said in a statement. “He did not say whether he supports Tom, Dick and Harry marrying, or whether he is 'evolving' in that direction. Perhaps he has to consult with his mentor on this issue, Mr. Joseph Biden of Delaware.”

“The time has finally come to pass a constitutional amendment affirming marriage as an institution reserved to the only two people who can naturally produce a family, namely a man and a woman,” he added.

Other social conservatives also jeered the president's move.

Tony Perkins of the Christian conservative Family Research Council (FRC) said Obama had just handed Mitt Romney “the key to social conservative support.”

“The President has provided a clear contrast between him and his challenger Mitt Romney,” Perkins said. “Romney, who has signed a pledge to support a marriage protection amendment to the U.S. Constitution, may have been handed the key to social conservative support by President Obama.”

(Related: Mitt Romney on Obama's gay marriage support: Other people have differing views.)

Brian Brown, the president of the National Organization for Marriage (NOM), also criticized the president: “God is the author of marriage, and we will not let an activist politician like Barack Obama who is beholden to gay marriage activists for campaign financing to turn marriage into something political that can be redefined according to presidential whim.”