Who has a Stonger Faith? McCain or Obama?

For Republican John McCain and Democrat Barack Obama, their appearances at a forum Saturday night at Warren's evangelical California megachurch bring risks along with rewards.

The event will play to one of Obama's strengths, talking about his Christian faith, but it will also underscore the gulf between his views and those of the most conservative Christian voters.

Many of McCain's positions are more in line with the evangelical worldview, but he is uncomfortable — and some critics say unconvincing — while talking about his personal beliefs.

The candidates will appear separately, spending one hour each with Warren, before coming together on stage for a handshake. The pastor, who does not endorse candidates, will be the only one asking questions.

Obama has proven adept at explaining how his Christian faith has shaped his policies. The church forum also gives him a perfect setting to counter the misperception that he is Muslim. A recent poll by the Pew Research Center for the People and the Press found that 12 percent of respondents believe the Illinois senator is Muslim.

However, Obama will inevitably be asked to explain his support for abortion rights and other issues that clash with conservative Christian theology.

No one expects Obama to lure the most traditional Christian voters from the GOP. Polls consistently show McCain winning frequent churchgoers by large margins. But in a close general election, Obama could win by taking a small percentage of the evangelical vote away from the GOP.