Barack Obama didn't choose just any Roman Catholic when he named Joe Biden his vice presidential running mate. He chose a weekly massgoer who once threatened to shove his rosary beads down the throat of the next Republican who said he wasn't religious.
Obama, in introducing his pick for the No. 2 spot, twice mentioned Biden's religious denomination. But how much of a boost could Biden's faith give the Democratic ticket?
In a country that is 24 percent Catholic—the largest single faith group—it's not that simple, because for years Catholics have not been the reliable Democrats they once were.
"The thing that is important to know about the Catholic vote," says John White at the Catholic University of America in Washington, "is there is no 'Catholic vote.' "
A professor of politics, White says the high-water mark for Catholic voters came in 1960, when Democrat John F. Kennedy made history as the first Catholic president, capturing 78 percent of their vote. Now, though, Catholic identity tends to be just one feature these believers bring into the voting booth, along with factors such as race, gender, class, education level, and sexual orientation.
Experts say conservative Catholics who oppose abortion and same-sex unions skew Republican. Liberals who support social justice causes and oppose war and the death penalty tend to be Democratic. Catholics of European heritage, such as the Irish, Italian, and Polish, have gravitated to the GOP as they've scaled the economic ladder and settled in suburbs. But Hispanic Catholics, a growing group, trend Democratic.
While there are two ends of the spectrum, says John Green, a senior fellow at the Pew Forum on Religion and Public Life, "there's also a large middle. And a lot of Catholics make their choice case by case, election by election."
In the past few decades, Catholics have swung back and forth between the parties in presidential contests. President Bush won a majority of them in 2004, after three successive wins by Democrats Al Gore and Bill Clinton. Before that, the GOP had a three-election winning streak, thanks to George H. W. Bush and Ronald Reagan. Earlier, Jimmy Carter claimed Catholics in 1976, as did Richard Nixon in 1972. "Since Lyndon Johnson's landslide election in 1964, there's been a slow trickling away of Catholics from the Democratic Party," White says.
He says a more pertinent cultural divide separates those who attend church regularly and those who don't. Regular churchgoers skew Republican. Then there are those for whom religion is more an interior phenomenon. White calls them the "My religion is for me, not for you" crowd and says that for them, church hierarchy is one moral voice but not the only one. And they are more apt to be Democratic.
Should Obama-Biden triumph in 2008, it would make history. The United States has never had a Catholic vice president. The list of major-party presidential nominees is also short. Kennedy prevailed after Al Smith, the Democrats' choice for the White House in 1928, fell short. Likewise, Democrat John Kerry lost the race in 2004.
Up to now, Catholic vice presidential nominees have not brought much luck to any ticket. They include Democrats Geraldine Ferraro, who was Walter Mondale's running mate in 1984, Sargent Shriver, who was George McGovern's pick in 1972 (after Tom Eagleton dropped out amid disclosures that he'd undergone electric shock treatments), and Ed Muskie, who was Hubert Humphrey's choice in 1968. Earlier, in 1964, Republican Barry Goldwater tapped William Miller for the No. 2 spot.
This year, non-Hispanic white Catholics, who political scientists say are more likely to vote than Hispanic Catholics, are evenly split between John McCain and Obama, according to a poll by the Pew Research Center. It found 45 percent backed McCain and 44 percent Obama.
That Obama is making a play for Catholics, while McCain courts them aggressively, is not surprising. The same poll found that among the all-important "undecideds," those for whom the sale has not yet closed, more than 1 in 5 is Catholic.
Most analysts think Biden might help Obama with some Catholics—but certainly not all of them.