From ABC News

What did Maher say that has drawn the protest from CWA?

Nance cites instances when Maher, a comedian whose show airs on HBO, reportedly called former Alaska Gov. Sarah Palin a “dumb twat” and Palin and Rep. Michelle Bachmann “boobs” and “two bimbos,” and said of a woman seen breast feeding in public, “don’t show me your tits!”  The comments were made in a satirical setting, but Limbaugh has said he was joking, too.

A spokesperson for Maher declined to comment when reached by ABC News.

“It’s never appropriate to degrade women, no matter whose side you’re on,” said Obama campaign spokesman Ben LaBolt in an email.

Michelle Malkin also addressed this

Mr. Maher, who disagrees with Sarah Palin’s politics, has called her a litany of adjectives inappropriate to repeat in any setting and are of the most derogatory of terms reserved for only violent verbal hate crimes against women.  We understand that he has donated $1 million dollars of his personal money paid to him through various businesses that thrive on the ratings of his hate speech to your Priorities USA Action to aid in your efforts to re-elect President Obama.