The enormous political clout wielded by evangelical Christians in the United States is usually seen from the outside as a coup for rightwing zealots against any agenda that might be called "progressive". But we should think again. The recent revelation that Michael Moore's Catholicism emerges in his latest film as a centrepiece of his critique of capitalism is really no surprise. The claim in Capitalism: A Love Story that free markets are inconsistent with Christianity has wrong-footed Moore's rightwing critics, but the right's bid to monopolise religion has been challenged for some time.

As Austen Ivereigh points out, Moore's anti-capitalist preaching is quite in keeping with Catholic traditions of social activism. What's less known is that evangelical Christian churches -- the supposed mainstay of rightwing politics in the US -- are showing a leftwards drift. In fact many commentators believe that the presidency of George W Bush, which undoubtedly revitalised conservative Christians, was possibly their last act as a major force in the political landscape. The "religious right" has long played a pernicious role in US politics. Its insistence that preachers should be interested only in saving souls -- a good alibi for neglecting the material needs of the poor -- has consistently been contradicted by their complicity in free markets and vocal opposition to abortion and gay rights. But this is not the only story to tell about American Christianity. Arguably Obama's election -- won in part due to the successful courtship of a large section of the religious vote -- suggests that it is not the most important one either.

Nearly every major social justice battle fought in the US has been supported, if not driven, by religious groups -- which in statistical terms overwhelmingly means Christians. It's widely known that the historically black church has been a key player in promoting justice for African Americans -- from the abolition of slavery to the civil rights movements -- as well as championing initiatives that support marginalised communities, both black and white. Beneath the more notorious rhetoric of Obama's former pastor, Reverend Jeremiah Wright, who at one point looked likely to irreparably fracture Obama's presidential bid, we can find him preaching the acceptance of homosexuality and the importance of works as well as faith. Wright's work at Trinity United Church of Christ, the church Obama was a member of for over 20 years, involves programmes for HIV/Aids sufferers, drug rehabilitation, and housing support for Chicago's impoverished South Side communities. That Obama's association with such a church should have been so potentially disastrous for his candidacy is deeply ironic. But in the end, Obama's religious identity did help him win votes.