Biden has long been an outspoken advocate for Irish-American issues and Obama has struggled to win over Irish-American voters, so part of the calculus that went into the choice of Biden was the hope that Biden can bring voters in places like his home town of Scranton, Pennsylvania into Obama's column. Between them, they mentioned "Scranton" five times and "Catholic" three times during the speech.
"He was the son of a single mom, who struggled to support herself and her kids and raised him to believe in America," Biden said about Obama. "I was different. I was an Irish Catholic kid from Scranton."
When he got to the convention and gave his speech on Wednesday night, Biden pointed to his mother, Catherine Eugene Finnegan Biden, sitting in the audience. Some conservative bloggers criticized Biden for referring to her as a great "American" in Denver when in the past he has complimented his mother - of Derry heritage - with being "quintessentially Irish."
"Biden 08 plagiarizes from Biden 06 - transforms his mother from Irish to American," one anti-Obama website railed.
Returning to his hometown of Scranton the Monday after the convention, Biden recounted that when he grew up there, "To be Irish was to be Catholic was to be Democrat."
Back at the convention, Senator Edward Kennedy, recovering from cancer treatment, made a surprise appearance and was greeted with a tumultuous ovation.
"I have come here tonight to stand with you to change America, to restore its future, to rise to our best ideals and to elect Barack Obama to the presidency of the United States," Kennedy said to a standing crowd.