With Iowa Republicans preparing to head to their overheated church basements for the Jan. 3 caucuses, today’s NBC-Marist poll shows Minnesota Representative Michele Bachmann in single digits, and former Speaker Newt Gingrich passing Texas Governor Rick Perry going the wrong way (down) through the low teens.

The poll also provides further confirmation of what everyone in Iowa is talking about -- former Pennsylvania Senator Rick Santorum’s timely surge. If it lasts, and Santorum lands in Iowa’s top tier, former Massachusetts Governor Mitt Romney will emerge from Iowa with something he hasn’t had through the previous months of this campaign: an articulate, socially conservative opponent who isn’t a clown and has a picture-perfect family life to rival Romney’s own.

In fact, if you were to bolt a conservative candidate together from spare parts -- and Santorum sometimes seems as if he has been -- you would get something akin to the former Pennsylvania senator. He has the conservative record and rhetoric, and the personal life, to appeal to Christian and economic conservatives. True, he’s done time in the toxic Capitol, but in his 12 years as a senator, few fought harder for conservative causes. He sponsored the partial birth abortion bill and championed welfare reform and Federalist Society-approved judicial appointments. He’s a hawk on defense, favors lower tax rates and wears his faith on both sleeves.

Stillborn Child

In a mid-December Public Policy Polling survey of likely caucus goers, Santorum had the best favorable-over-unfavorable ratio of any of the candidates -- 56/29. (Romney’s, by comparison, was 49/40.) Yet Santorum proves that having high favorability is not the same as being liked. Voters don’t doubt that he’s genuine -- the curse that afflicts Romney. It’s possible, though, that they find him a tad intense.

He has related, for instance, how he brought his child, stillborn at 20 weeks, home to meet his young children before the burial. It doesn’t help that Santorum’s default facial expression is a pout, which has been on regular display in the Republican debates, where he scolds his rivals for their myriad imperfections. He’s a bit like the unappealing kid your parents wished you’d hang out with more, turning his homework in early and asking Teacher for more.

Whatever the reasons, Santorum has had a tough time winning affection from the most important bloc of Iowa Republicans: evangelical conservatives. For the past year, they’ve resisted Santorum, even though he has visited all of Iowa’s 99 counties, some more than once, and held close to 400 town hall meetings. Instead, they have fawned over Bachmann and Perry before venturing into the red-light districts of Herman Cain and Gingrich, whose seemingly insatiable need for repentance might have taxed a less forgiving electorate.

Ultimately, Santorum has been hampered by doubts about his ability to win. Since few thought he could, the burden of proof became a self-fulfilling prophecy, keeping him from attracting the financial support necessary to finance organization, advertising and the aura of a contender.

His spectacular loss in 2006 hasn’t helped. Running against Robert Casey, Jr., the son of one of Pennsylvania’s most popular governors, in a year that was terrible for Republicans nationwide, Santorum lost his reelection bid by a whopping 18 percentage points. He’s been out of elective office ever since.

The Dog Whistle

After the implosion of Bachmann and the struggles of Perry, and with Gingrich descending faster than the New Year’s ball in Times Square, evangelical conservatives appear to be finding their way to Santorum. Last week, he won the support of one of Iowa’s most powerful evangelical Republicans, Bob Vander Plaats, who chaired former Arkansas Governor Mike Huckabee’s winning Iowa campaign in 2008.

Could Santorum’s moment have arrived? “In the next five days the social conservative dog whistle will blow loud for Santorum,” Republican strategist Mike Murphy predicted on Dec. 29. “He can keep rising, could even catch Mitt.”

Given the Iowa expectations game, Santorum need only make it into the same sentence with frontrunners Romney and Texas Representative Ron Paul, whose cranky, conspiracy-prone and isolationist views will not carry him far beyond Iowa.

Santorum is so confident of emerging from the pile in Iowa that he just committed money for television ads in New Hampshire, which votes on Jan. 10. Meanwhile, in Iowa this week, he received the kind of validation that every candidate craves. Perry just launched a negative radio ad specifically targeting Santorum. He’s arrived.

(Margaret Carlson is a Bloomberg View columnist. The opinions expressed are her own.)

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To contact the writer of this article: Margaret Carlson in Washington at mcarlson3@bloomberg.net.

To contact the editor responsible for this article: Francis Wilkinson at fwilkinson1@bloomberg.net.