Mitt Romney achieved a rare political feat when he delivered his “Don’t let my Mormonism cost me this election” speech. With barely twenty minutes of disjointed rhetoric about the role of faith in public life, the former Massachusetts governor made a convincing case, both to religious zealots who would erase the line of separation between church and state and to secularists who cherish that line, that the fading GOP front-runner is a poor choice to rest his hand on any book of Scripture come January 20, 2009. Romney did this by speaking as a politician rather than as a statesman in the mold of the Catholic senator from Massachusetts who told Baptist preachers in 1960 that the demarcation between religious belief and governing principle must remain “absolute.” Where John Kennedy majestically promised to reject religious dogma in favor of the common good, Romney merely pleaded that a particular candidate–himself–not be “rejected because of his faith.”

Even as Romney demanded tolerance of his minority faith, he dismissed believing and nonbelieving secularists–“Americans acknowledge that liberty is a gift of God, not an indulgence of government”–in a manner suggesting that the line between church and state would indeed blur in a Romney administration. How was it that he struck so many wrong notes? Well, unlike Kennedy, Romney was not speaking to the mass of voters; rather, he was begging a small clique–evangelical Republicans who participate in early caucuses and primaries–to stay on his GOP bandwagon rather than hop on the church bus driven by former Arkansas Governor Mike Huckabee.

Unspoken by Romney–or most analysts of the Huckabee surge in Iowa, South Carolina and national polls, which now place him second only to Rudy Giuliani–is a key to the preacher’s progress: an embrace of precisely the sort of religious test America’s founders sought to guard against. It’s not just that Huckabee is a confirmed creationist whose policy pronouncements would make Pat Robertson blush (he describes homosexuality as a sin, “just as lying is sinful and stealing is sinful,” and condemns both same-sex marriage and divorce). The fact is, Huckabee and his backers have an ugly tendency to question the faith of their foes. When Fred Thompson’s campaign criticized him on a Sunday, Huckabee surrounded himself with ministers and chirped, “Most of us were in church. He was cranking out press releases.” When Huckabee and Sam Brownback competed for religious-right backing in Iowa’s August straw poll, e-mails from a prominent pastor reminded evangelicals that Brownback had converted to Catholicism and urged support for Huckabee as “one of us.” Requests that Huckabee denounce what Brownback’s organization called a “whisper campaign” of “bigoted slurs aimed at a person’s faith” were not met to the satisfaction of Brownback, who later quit the race and endorsed John McCain.

But Thompson and Brownback got off easy compared with Romney, who has long been in the cross hairs of the Huckabee campaign, which runs ads identifying its candidate as “a Christian leader.” Huckabee avoids explicit pokes at Romney’s faith while asking provocative questions about Mormonism, rarely distancing himself from backers who suggest that evangelicals could do better than to vote for a member of the Church of Jesus Christ of Latter-day Saints. Huckabee’s Iowa supporters openly suggest at campaign events that Romney’s “going to be acting on an anti-Christian faith as the basis of his decision-making.” The Arkansan’s Iowa campaign co-chair, Daniel Carroll, says Christians prefer his man over Romney because Huckabee “prays to the God of the Bible.” Huckabee simply suggests that God prefers him. After being introduced in late November by Jerry Falwell Jr. as a candidate who “believes like we do,” Huckabee told a crowd at Falwell’s Liberty University, “There’s only one explanation for [my surge], and it’s not a human one. It’s the same power that helped a little boy with two fish and five loaves feed a crowd of 5,000 people.”

In the GOP race, it’s not Romney’s Mormonism that poses a threat to the core values of a secular nation. It is the messianic candidacy of Mike Huckabee, which seeks to apply the “religious test” for government service, a test the founders feared would be the undoing of the American experiment.