Herman Cain, Texas Gov. Rick Perry, Sarah Palin and now, it seems, Donald Trump have lined up behind Newt Gingrich. It’s convenient to have a candidate like Gingrich who attracts the unserious, the unpresidential, the uninformed and the unpalatable all in one convenient locale. It saves the time and effort needed to determine who is a credible Republican and who is not (Gingrich supporters). The move is yet another boost for Rick Santorum, who definitely is in the category of responsible and credible candidates (whatever you think of his views) and has been struggling to wean the base off its attraction to Gingrich.

Referring to this December report on the least desirable endorsements (“According to a Marist poll, 79 percent of New Hampshire voters say getting Trump’s support would make them less likely or no more likely to vote for him or her”), Jesse Benton, spokesman for Rep. Ron Paul (R-Tex.), e-mails me, “Poor Newt. Based on the polling I’ve seen, he stands to lose 5 points from this circus act.” As for Trump, Benton cracks, “I didn’t think it was possible for Trump to lower his credibility, but somehow, he just did.”

There is a weird commonality among Cain, Trump and Gingrich — an unseemly pattern of behavior with women. Perhaps that’s simply one manifestation of their egomania. And all of these pro-Newt characters share a penchant for extreme, nasty rhetoric with a disdain for productive governance. This is all about THEM and their PR machines.

Santorum, most especially, should press the point: Gingrich, as always, is taking the party for a joyride (or is it an ego trip?). If conservatives who don’t care for Mitt Romney but want a candidate and not a joke, they can choose him. Just yesterday at least one poll had Santorum besting Romney in Ohio. Public Policy Polling finds:

[Obama] leads Mitt Romney by 7 points (49-42), Newt Gingrich by 12 (51-39), Ron Paul by 10 (48-38), and Rick Santorum performs best, trailing Obama by 6 points (48-42). . . . All Republican candidates have net negative favorability ratings, some of them quite large – Newt Gingrich is at 25-59, Ron Paul is at 27-57, Romney’s at 28-56, and Santorum again performs best at 35-48.

PPP also had good news for Santorum in Missouri:

Santorum has a 63-21 favorability spread to Gingrich’s 52-32, Romney’s 46-36, and Paul’s 28-57. On the actual primary ballot, for which Gingrich did not qualify, Santorum leads with 45% to Romney’s 34% and Paul’s 13%. In the caucus, in which Gingrich can compete, Santorum falls to second at 28% behind the former speaker’s 30% and ahead of Romney’s 24% and Paul’s 11%. Head-to-head, Gingrich would defeat Romney in the state, 43-42, but Santorum would, 50-37. That is because Santorum’s supporters only go for Gingrich by eight points over Romney, but Gingrich’s vote for Santorum by 28 points.

Now, it seems, is precisely the right time for Santorum to push his way past Gingrich and make the pitch to conservative voters that he’s not merely the only consistent conservative alternative to Romney, he’s also the only one who’s not a joke. Really, what’s next for Newt — a Duke Cunningham endorsement from a jail cell?