Bayh is a strong supporter of his Senate colleague, Hillary Clinton, and has generally voted in favor of legal abortion. But he did vote in favor of banning the procedure known as partial-birth abortion.

Ellen Malcolm, president of Emily's List, a political action committee that contributes to female candidates, told Gannett News Service that Bayh "has lost the support of some in the pro-choice community." Similar objections were made in 2000 when Bayh was on a short list as Al Gore's running mate.

Last year, the National Abortion Rights Action League gave Bayh a 100 percent rating. There were no votes on late-term abortions.

"Obviously, we will convey to Sen. Clinton that we think it's important to have a pro-choice person on the ticket, but ultimately it's going to be her decision on who the running mate is," Malcolm said. "There are going to be a number of factors for her to weigh."