|PIC1|US presidential hopeful John McCain's pick for vice president will be of crucial importance to value voters when they go to the polls this November, believes an influential evangelical leader.

The running mate selection is the "most important" decision that Republican presumptive nominee McCain makes in his entire campaign, Richard Land of the Southern Baptist Convention's Ethics and Religious Liberty Commission told CBS News.

If McCain picks a pro-choice running mate, Land said, it will only confirm the mistrust many evangelicals already feel toward the candidate some criticise as too liberal.

"[H]e has no room for error, no margin for doubt," noted the head of the public policy arm of the nation's largest Protestant denomination.

Southern Baptists and many evangelicals, Land said, are looking at the prospective vice president primarily on the sanctity of human life, the traditional family and religious freedom.

Some vice presidential candidates that religious conservatives would support include Governor Palin of Alaska, who said she never considered an abortion even though her child has Downs Syndrome, and former Arkansas Governor Mike Huckabee, who during his run this election was highly popular among evangelicals.

Regarding Mitt Romney, Land acknowledged that some evangelicals would have a problem with his Mormon faith. But as for himself, Land said although he does not consider Mormonism a Christian faith, he does not believe that disqualifies someone from being president or vice president.

Another name Land offered was Republican Eric Cantor, who is the fourth highest person in the House leadership. Cantor is a practising Jew who has a 100 per cent pro-life voting record.

According to a poll conducted by the SBC's research arm in June, 80 per cent of Southern Baptist pastors said they plan to vote for McCain. Only one per cent said they plan to vote for Obama, and the rest were undecided.

Land had some unfavourable things to say about Obama, whom he regards as extreme in his support for abortion.

In particular, the evangelical leader found it troubling that the Illinois senator previously opposed legislation that would require a doctor who performs an abortion on a late term fetus to save the baby's life if it is born alive.

"And Senator Obama opposed that bill," Land said. "I don't know how you can get more pro-abortion than that. And I can't imagine even John Kerry doing that. And, of course, in addition to which, he voted against the partial-birth abortion ban."

Land emphasised that he does not make political endorsement and would not explicitly say whom he would support. He said, however, that he would vote for candidates that reflect his values and leave people to "connect their own dots".