Casey was set to speak during the convention's session Tuesday night, his office said. He is the son of the late Pennsylvania Gov. Robert P. Casey, who was not given a marquee speaking spot at the 1992 convention because of his anti-abortion views.
Democratic presidential candidate Barack Obama supports abortion rights. Casey endorsed Obama over Sen. Hillary Rodham Clinton, also an abortion-rights supporter, and campaigned with Obama throughout Pennsylvania. Clinton trounced Obama in the primary but not by a big enough margin to thwart his bid for the nomination.
Casey said in a statement that he was honored to have the opportunity to speak. Neither he nor the Obama campaign indicated what would be the topic of his speech.
"Our country faces very grave economic, military and foreign policy challenges and many Americans of all political parties will vote for a change in November. Barack Obama is the only candidate who offers that change of direction we need," Casey said.
Craig Schirmer, Obama's Pennsylvania director, said in a statement that having Casey speak reflects Obama's desire to unify the party and country.
The proposed Democratic platform to be voted on by delegates has a plank for abortion rights that is stronger than usual. "The Democratic Party strongly and unequivocally supports Roe v. Wade and a woman's right to choose a safe and legal abortion, regardless of ability to pay, and we oppose any and all efforts to weaken or undermine that right," it says.
In the past the plank has said abortion should be safe, legal and "rare." This year the party also pledges to ensure access to adoption programs, prenatal and postnatal care and income support programs for expectant mothers who need the help.
At the 2000 convention, Casey and his brother, Pat, spoke in tribute to their father, who had died earlier that year.
The Obama campaign also announced that Pennsylvania Gov. Ed Rendell would speak on the second day of the convention. Rendell was a major advocate for Clinton during the Democratic primary, but has since said he supports Obama.
