Rep. Steve King, an influential Republican congressman from western Iowa, has not endorsed a presidential candidate. But in the final sprint toward Tuesday’s caucuses, he is urging conservatives to stay away from Rep. Ron Paul of Texas.

King is adamant that Paul’s “isolationist” views are a threat to the country.

“In these last few days, the public and especially the activists in Iowa need to understand what Ron Paul would do if he became commander-in-chief,” King says. ‘I don’t think some of the responsible caucus-goers, many of whom support him, understand what he means on [foreign policy] and what he would do as president, pulling us out of places around the world.”

As Iowans make their final decision, King worries that Paul’s popularity on fiscal issues could overshadow his “blind spot” on foreign policy. “Our presence around the globe has been paid for by a tremendous amount of blood and treasure,” he says. “We are the force for security around the globe. If we had a commander-in-chief who pulled back military operations and brought it all back to the United States, and took a position that we would not intervene in foreign conflicts and only if attacked on our shores, there would be a huge power vacuum.”

“That giant sucking sound would draw in the Chinese, the Russians, Hugo Chavez, and others up into our shores and into the Caribbean,” King says, speculating on a Paul administration. “To paint an image of what I think it looks like under a Ron Paul presidency, it would be Iranian nuclear missiles placed in Cuba and Katyusha rockets in Tijuana. Neither of those situations would bother Ron Paul and that’s a calamity, that’s catastrophic.”

In an interview with National Review Online on Friday, King also discussed a variety of caucus-related topics, from his latest meeting with Bachmann to Santorum’s likely finish.

Santorum’s surge: “I think Santorum has arrived in third place,” King says. “His ascension has been impressive. The question is whether he can win. I’m not as much of an optimist about that; I don’t see that happening. But his timing has been excellent. Another week wouldn’t help Rick Santorum. He’s already done everything he could do. In the end, I think he’ll get to third, and that will be a result of hard work, of pounding the ground.” In sparsely-populated western Iowa, Santorum, a former Pennsylvania senator, has found a way to connect with Midwestern conservatives, King says, making a national race very local, from visiting all of Iowa’s 99 counties to pheasant hunting with local pols. “He’s even a good shot,” King chuckles.

Romney’s rise: “Romney has solidified his position,” King says. “People are coming home to the idea of who can beat Obama. That question hangs out there and it’s helping Romney.” Indeed, as Gingrich slips, “the race, right now, has become Romney-Santorum,” he says. “And it’s a big help to Romney to have the social conservatives split like they are — Santorum, Bachmann, Perry, and to some extent, Newt Gingrich.” Romney, he notes, performed ably in Iowa last cycle, placing second to Mike Huckabee. After months of quiet campaigning, “Romney is now making a serious play for Iowa, turning up his effort,” King says. “If he wins it, he’ll have earned it.”

Gingrich’s tumble: King attributes Gingrich’s slide in the Iowa polls to the barrage of negative spots on the state’s airwaves. But Gingrich’s problems, he says, are deeper than 30-second television ads. He cites Gingrich’s (lack of a) message as the real issue. Instead of offering a focused platform, King says the former speaker’s proposals and the accompanying rhetoric have been muddled. “In politics, they always say pick five things, or three things if possible, and drive those three things, make people identify you with a core message,” he says. “I don’t think Gingrich has created those kinds of points for his campaign.” And at this point, “the inertia has him going in the other direction and I don’t think he’ll climb back.”

The Sorenson switch: King huddled with Bachmann, his closest congressional ally, in Early, Iowa on Friday afternoon. He did not endorse his House colleague during a brief press conference but he did chat with her on her bus following the event. Behind closed doors, he offered her support as she deals with her latest campaign crisis: the departure of her Iowa chairman, state senator Kent Sorenson. Sorenson recently joined the Paul campaign and soon after, Bachmann accused him of switching for financial reasons, musing that Paul’s advisers offered money in exchange for his support. Sorenson, for his part, has repeatedly denied the charge.

Regardless of which party is right, King stands by Bachmann. “Kent Sorenson’s timing on this, and the act itself, was just wrong,” he says. “Even if he had the deepest of convictions that he needed to support to Ron Paul, he shouldn’t have done it. You don’t show up at a Bachmann campaign rally, in your hometown, and two hours later show up at a Ron Paul rally and endorse him. Even if you feel absolutely compelled to act this way, you should go underground for five days and keep your integrity intact. He didn’t do that. I tried to put myself in his shoes, to think about his potential rationale, but I couldn’t see it, nor do I see how money was not a part of his decision. In any case, it was a large mistake by Kent Sorenson. Any benefits that he gets will not offset the damage that he has done to himself.”

Bachmann’s struggle: “I don’t know if I can explain it,” King says, but he wonders whether her inability to generate wide support in Iowa is due to her gender. “There is that question among evangelicals about whether a woman should be president,” he says. “I don’t question it, and think both men and women should be considered,” but in Iowa, “that is a piece of the puzzle.” Beyond that, Bachmann, he says, never found a way to hold onto the momentum she gained, albeit briefly, after winning the Ames straw poll in August. “As each of the frontrunners broke for the top of the hill, especially Rick Perry, it became hard for her to break back into the middle of all of that, maybe impossible,” he says. “Now that people are down to settling this thing out, Santorum has earned a lot of the support that might otherwise have gone to Bachmann.”