Just a day after he was announced as Barack Obama's running mate, Sen. Joe Biden was back in Delaware, taking his usual seat in the pews of St. Joseph on the Brandywine in the small community of Greenville.
That he would participate in a Roman Catholic Mass so soon after being added to the Democratic ticket was of little surprise. Biden once vowed that "the next Republican that tells me I'm not religious, I'm going to shove my rosary down their throat."
Similar passions lie behind the efforts of the Obama campaign and Democratic strategists this year to win over Catholic voters, considered by many to be a crucial constituency that could determine the next president. Emotions have grown heated, with Biden under attack from national Catholic groups for his views on abortion, and Republican vice presidential nominee Sarah Palin energizing many socially conservative voters.
One-quarter of American voters - about 30 million - identify themselves as Catholics. The percentage is even higher in the battleground states of Pennsylvania, Ohio, New Mexico and Florida.
The top vote-getter in the past nine presidential elections has won a majority of the Catholic vote. If Obama and Biden - who would be the first Catholic vice president - are to win in November, many analysts say it will be because Democrats successfully wooed undecided Catholics, including those grappling with the ticket's support of abortion rights.
"There's a chunk of about 20 percent who can swing one way or the other and they will determine the result of the election," predicted the Rev. Tom Reese, a Jesuit priest and political scientist at the Woodstock Theological Center at Georgetown University. "It's a very volatile group, but it's become clear that the Democrats cannot win the presidency without the Catholic vote."
Biden was tapped primarily for his foreign affairs background, a counter to criticism that Obama is not ready to be president. But Biden's Catholic background was also a factor.
Many Democrats have vowed not to cede the votes of devout Catholics and other Christians this year, after two narrow defeats in elections in which President Bush and his political adviser Karl Rove reached out to religious voters with unsurpassed vigor.
The diversity of Catholics, however, poses a challenge for strategists of both parties.
