Scott Walker (47): The second-term governor of Wisconsin is the son of a Baptist preacher and the only presidential candidate without a college degree, as he dropped out of Marquette University after three years.

Walker remained a Baptist as an adult, and was a deacon at Underwood Memorial Baptist Church in Wauwatosa, Wisconsin, until 2005. At that time the family moved to Meadowbrook, a non-denominational evangelical church. It appears that they decided to leave Underwood because it had moved in a more liberal direction, although Walker said it was primarily for their two children. He has spoken a number of times about the significance of his morning devotionals and thanked his supporters for praying for him.

"My relationship with God drives every major decision in my life" he said in a statement to the New York Times. Speaking at a breakfast for Christian businessmen in 2009 (before he became governor), he reflected on the importance of the hymn 'Trust and Obey' in his faith journey. A key moment was deciding for himself to follow Christ at the age of 13: "Before that it was kind of like following the rules, but just because that's the right thing to do, this is saying I have just...said I am going to trust in you, Christ, to tell me where to go and to the best of my ability I'm going to obey where you lead me. And that has made all the difference in the world to me. Through good times and bad." Consequently, he believes God told him who he should marry and when he should run for governor.

On how his faith and politics relate, he said in an interview with the Christian Post: "There's not a play card, if you will, that tells me how to vote or how to act on certain issues. So, it's not like issue by issue it drives me. But, the larger context, not only the policy decisions I make, but how I make them, how I interact with people, how I treat people. All of those things are, without a doubt, driven by my faith."

His experience as governor hasn't been entirely straightforward. His opposition to collective bargaining rights for public sector workers in his state led to huge protests and a recall election in 2012, which he won. Speaking before the June 2012 election in an interview with CBN's 'The Brody File' he said: "We realize that all this is just a temporary thing and God's got a plan for us that, who knows where it might be, beyond just serving as governor of this state, but if we stay true to that, there's always comfort...God's grace is always abundant no matter what you do."

Since the decision of the Supreme Court to legalise gay marriage, Walker has called for a constitutional amendment to allow states to define marriage and "protect the institution of marriage". He is also pro-life and has recently supported a bill to reduce the abortion limit in Wisconsin to 20 weeks, without any exceptions for the victims of rape or incest.

He has emphasised his commitment to tackling radical Islamic terrorism and working on building a more positive relationship with Israel.