Sixteen years after his father was denied a speaking part at a Democratic convention because his anti-abortion views led him to oppose Bill Clinton’s candidacy, Senator Bob Casey Jr. of Pennsylvania told the convention Tuesday night that Senator Barack Obama could bring together supporters and opponents of abortion rights.

Mr. Casey is, like his father, former Gov. Robert P. Casey of Pennsylvania, a Roman Catholic who opposes abortion. He was invited to speak as part of a broad effort by the Obama campaign to reach out to religious voters and anti-abortion Democrats and independents.

Mr. Casey spent most of his seven minutes at the podium praising Mr. Obama and saying that his Republican opponent, Senator John McCain, would extend the Bush-Cheney record.

But he also addressed the abortion question head on. “Barack Obama and I have an honest disagreement on the issue of abortion,” Mr. Casey said. “But the fact that I’m speaking here tonight is testament to Barack’s ability to show respect for the views of people who may disagree with him.”