by Evie Stone

Tonight's theme is the economy — the official title is "Renewing America's Promise". And Pennsylvania Senator Bob Casey Jr.'s speech kept up the assault on George Bush and John McCain. Barack Obama, he said, is "one of us".

Casey summed up McCain's record of frequent votes in support of the President's policies with a quick one-liner: "That's not a maverick. That's a sidekick." And he twice led the crowd into rousing chants of "four more months!"

But Casey's appearance held significance beyond his ably delivered jabs at the GOP. His father, then-PA Gov. Robert Casey Sr., was famously denied a speaking slot at the 1992 Democratic Convention. Rumors at the time suggested that Casey Senior was persona non grata at the podium because he was pro-life, though the Bill Clinton campaign maintained that it was because he was not an early Clinton supporter.

Casey Jr. is pro-life as well, and was one of Obama's most active surrogates during this year's hard-fought Pennsylvania primary against Hillary Clinton. Casey made a veiled reference to the 1992 snubbing with this line:

Barack Obama and I have an honest disagreement on the issue of abortion. 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.

Obama is pro-choice and highly rated by the abortion-rights advocacy group NARAL. But his campaign has made a point of reaching out to Catholics and moderate evangelicals whose positions on other social issues like war, poverty, and the death penalty align with the Democratic platform. Bob Casey Jr.'s appearance tonight is another olive branch to those voters.