The Democrats' problem goes beyond simply being irreligious. There's an undercurrent of hostility toward religion in the highest ranks of the party. The Democrats' dismissal of Bush's "faith-based initiative" is just one example of their hostility. Even on an issue like abortion rights, on which Democrats are with the majority of the public, intolerance of any dissent has alienated a mainstay of the New Deal coalition, Roman Catholics.
That's ironic, because the last time the Democrats were in as bad a shape as they are today, 1928, the issue that did them in was religion, specifically the nomination of the Catholic Al Smith for president. Then, the party seemed too religious; now its problem is no religion at all. The gamble Democrats made in 1928, nominating a Catholic for president, paid off handsomely in the half century after Smith, as legions of Irish, Italian and Eastern European Catholics joined Southern and Western Protestants to vote again and again for Democratic majorities. John F. Kennedy's Catholicism is now regarded as crucial to his election in 1960, and he remains the last non-Southern Democrat to win the White House.
This is flat wrong. Last surveys I saw, 51% of WOMEN were now "pro-life," and a majority of men have always been. I don't know of one single poll that supports this statement.
Actually, this is no longer true, and the DemocRats are NOT with the majority of the public. About 75% respond "YES" when asked if life begins at conception. This is indeed inconsistent with the approximately 50% who say they want to allow abortions under limited conditions, but the majority DO contend that unrestricted abortion up until the moment of birth should be outlawed.