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Tonight Vice President Joe Biden and Congressman Paul Ryan take to the stage in Danville, Kentucky for the one and only vice-presidential debate. The debate gives the two a chance to highlight their many differences in policy, but the two have one fundamental thing in common: their faith.

This is the first time two Roman Catholics have faced off in the quest for the White House. And though it may be a historic moment for American Catholics, neither candidate can count on winning the Catholic vote.

For more on this we're joined by John Kenneth White, he is a professor of Politics at Catholic University in Washington DC.