Several women's groups have joined Sarah Palin's fight with David Letterman over his joke that Palin's daughter got "knocked up" by Alex Rodriguez during their recent trip to New York.

"It's worse than poor taste; it reflects ugliness in him. He would never say something like that about a liberal woman," president of Concerned Women for America Wendy Wright said in a statement. "But rather than deal with issues and ideas, he denigrates her as a human being."

The Alaska governor characterized Letterman's jokes as a reference to "statutory rape" since the only child with her at the game was her 14-year-old daughter, Willow. Letterman said the following night that the joke was in "poor taste," but he says he was joking about 18-year-old Bristol Palin, not Willow.

Palin appeared on NBC's Today show today, calling Letterman's apology "a weak excuse" and saying they were "a degrading comment on all young women."

"A generally understood rule of politics is that the children are off-limits," said Marjorie Dannenfelser, president of the Susan B. Anthony List. "Why are Palin's children an exception?"

Even the National Organization for Women has taken to defending Palin. "The sexualization of girls and women in the media is reaching new lows these days—it is exploitative and has a negative effect on how all women and girls are perceived and how they view themselves," the statement says.

Letterman had also joked that Palin had the style of a "slutty flight attendant." She has declined an invitation by Letterman to appear on his show.