It's being called the Saturday night showdown at Saddleback; the fourth largest church in the nation, Saddleback Church in Lake Forest, Ca., is the sight for a high stakes appearance by John McCain (web|news|bio) and Barack Obama (web|news|bio) .

The candidates will be questioned about their faith and values by one of America's most influential pastors, Rick Warren. Both candidates are expected to answer questions about their character, competence and experience while also trying to sway the block of voters that carried Bush to victory.

For John McCain, he has not always seemed comfortable talking about his faith. "I am unashamed and unembarrassed about my deep faith in God, but I do not obviously try to impose my views on others," McCain said. In fact, McCain's past relationships with some conservative Christian leaders has been rocky, and he is not polling as well with evangelicals as he would like.

On the other side, Barack Obama seems to be more comfortable talking about religion. "I came to see my faith as being both a personal commitment to Christ and a commitment to my community," Obama said. However, rumors that he is a Muslim, his controversial formal pastor and his liberal views on abortion have complicated his efforts to win over evangelical voters.

Pastor Warren says Saturday's forum will give both candidates an opportunity to open their hearts, because as he says, "Many evangelists think neither of these guys [Obama or McCain] are evangelical." Warren says while many evangelicals like McCain and Obama, they are really not sure where they stand on certain issues.

That is why Pastor Warren hopes to hear more from the candidates on Saturday. "I want to hear a person say that it's not a religion; it's a relationship. I've had a personal relationship with Christ now for almost 50 years....I talk to him all the time." 

The California event comes after a day of worship in the District. Thousands converged on the National Mall for the prayer gathering called, "The Call." The event is held on the Mall from 10 a.m. until 10 p.m Saturday, and its purpose is to assemble and pray for the nation's future. The faithful there today said they are eager to hear what the candidates have to say at Saddleback, and believe religion and value will be a deciding factor for voters in November.

"It's good to have a man of God that has values in his heart that stand on the principal of God," said one worshiper.

However, speaking in Leesburg Saturday, avid Obama supporter, Virginia Governor Tim Kaine says he isn't so sure religion will sway voters one way or the other. "There are two fundamental issues facing Americans right now, which is an economy that is suffering under some very serious challenges, and we got huge national security challenges."

The two presidential hopefuls will each discuss the issue of faith separately on the stage in California, but they are expected to exchange a handshake before the switch.