Conservative commentator and former Republican presidential candidate Pat Buchanan says Ron Paul will likely win the Jan. 3 Iowa caucuses, and that a poor showing by Newt Gingrich would be a death knell for his struggling campaign.

“I’ll say this: if Newt comes in third, his surge is done,” he told The Daily Caller.

Buchanan, who surged to a second place showing in the 1996 Iowa caucuses before winning the New Hampshire primary, said that the Texas congressman is a “slight favorite” over Romney to win the caucuses.

If Paul wins and Romney finishes in second place, Buchanan said the former Massachusetts governor would still be well on his way to capturing the nomination.

“If Ron Paul wins Iowa, Romney wins Iowa,” Buchanan said, because “Romney should still win New Hampshire.”

“And Newt,” he said, “who was the candidate, as of a month ago, who could probably have taken three out of the first four contests, the strongest candidate as of a month ago against Romney, will really be set back dramatically if he comes in third.”

Buchanan said Gingrich is probably suffering from the deluge of television ads attacking him in Iowa, and that without a victory either there or in New Hampshire, the former speaker is extremely unlikely to win the crucial Jan. 21 South Carolina primary. (RELATED: Full coverage of the Iowa caucuses)

“My guess is that the pounding on Newt is probably going to work with a lot of those folks who came out for him because they thought this is the authentic conservative,” Buchanan said. “And they found out about the $1.6 million from Freddie Mac, and they decided maybe not.”

“You’ll notice that the folks who win South Carolina have won either New Hampshire or Iowa,” he noted. “And if Newt loses them both, I think that’ll be hard for him to maintain, even though he’s got quite a lead in South Carolina.”

Despite his own come-from-behind surge in the week leading up to ’96 Iowa caucuses, Buchanan said he isn’t bullish on the chances of second-tier candidates like former Pennsylvania Sen. Rick Santorum or Texas Gov. Rick Perry.

Santorum, he observed, is still stuck behind several other candidates and doesn’t have much time to rise in the polls. And while he said Perry has lots of money and a “great message” for Iowa voters, he’s skeptical that the Texas governor can translate that into actual votes.

“He may be able to do it, but it’s hard for me to see how he wins,” Buchanan said of Perry. “If he does, it would be enormously dramatic, and that would really kill Newt. Then there’s a rival to Newt who people will say can be the non-Romney conservative.”

“If Perry rises to beat Newt, I think that’s it for Newt,” he said.

A Public Policy Polling survey released Tuesday showed Paul leading the Republican field in Iowa with 24 percent support, followed by Romney at 20 percent, Gingrich at 13 percent, Minnesota Rep. Michele Bachmann at 11 percent, and Santorum and Perry at 10 percent.

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