Can Biden help Obama woo the Catholic vote?

Democratic vice presidential candidate Joe Biden (D-DE) arrives in the convention hall at the 2008 Democratic National Convention in Denver, Colorado August 25, 2008.

DALLAS (Reuters) - Can Joe Biden bring his Catholic brethren into Barack Obama's fold?

Biden, the Democratic vice presidential candidate and an Irish Catholic from a Pennsylvania working-class background, could also win over blue-collar workers who backed Obama's party rival for the White House, Hillary Clinton.

"If we just focus on the religious element, adding Biden to the Democratic ticket was an extremely smart move," said Michael Lindsay of Rice University in Houston. Obama made Biden his running mate on Saturday.

"Biden has ties in a very important swing state, Pennsylvania, where Catholics are the biggest constituency whose votes are up for grabs," Lindsay told Reuters.

U.S. presidential elections are often decided by swing states that move from party to party. Catholics have been a swing vote also for decades. Opinion polls show white Catholics evenly split between Obama and Republican John McCain.

John Kennedy became America's only Catholic president in 1961. If elected, Biden would be the first Catholic vice president. House Speaker Nancy Pelosi, who is next in line to the president after the vice president, is also a Catholic.

Faith features in U.S. elections despite a formal separation of church and state in the workings of government. Candidates are often asked about the role of faith in their lives and how it might shape their presidencies.

Biden's broad support for abortion rights could help with more liberal Catholics while his opposition to late-term abortions could attract those who are uncomfortable with the procedure but don't vote on it.

ABORTION ISSUE

Opinion polls show that abortion, a traditionally divisive issue for Americans, is less of a factor for most people in this election than the economy, the Iraq war and health care, which top their priorities.

A Catholic candidate who speaks with passion about his religion, such as Biden, might also attract blue collar Hispanic voters, a majority of whom are Catholic.

Abortion may be more of a political minefield -- Catholic doctrine is strongly opposed to it -- but Catholics who oppose abortion rights and vote as such already are squarely in the Republican camp.

"There is a broader group of Catholics who have pro-life sympathies but who don't vote exclusively on that issue and in that case Biden may be an appealing candidate," said Allen Hertzke, a professor of political science at the University of Oklahoma in Norman.

"And the fact that he has opposed late-term abortions gives him some talking points which Obama doesn't have," he said.

Opinion polls have shown a close battle for the Catholic vote at the national level with a slight edge for Obama. Catholics account for nearly a quarter of U.S. adults.

The electoral clout of the Catholic vote is somewhat diluted by its distribution.

According to a report by the Center for Applied Research in the Apostolate at Georgetown University in Washington, nearly four in 10 U.S. Catholics live in New York, California and Texas, none of which are closely contested.

The report said states "where the Catholic vote could make a real difference are Florida, Ohio and Louisiana."

(Editing by Howard Goller, and David Storey)