Byron York

Social conservatives who are inclined to support Gingrich point out that he has presented himself as a more mature, more faithful man for several years now -- so the new Gingrich is not part of what is known in Iowa politics as a road to Des Moines conversion. But there's no doubt that some social conservatives will never get past Gingrich's rocky personal life; how many are among that number is still an open question.

So despite all the progress he has made -- he's now leading in the RealClearPolitics average of Iowa polls as well as national surveys -- Gingrich faces a tricky next few weeks. He not only hasn't fully convinced much-needed potential supporters of his new faithfulness, he also has yet to feel the full effects of new revelations about his activities as a Washington insider.

On the other hand, Gingrich remains the most formidable presence in Republican debates and, given the falls of Bachmann, Perry and Cain, and longshot nature of Rick Santorum and Ron Paul, there might be no one left to supplant him in the role of main challenger to Mitt Romney. Either Santorum or Paul will have a boomlet, or one of the fallen will have to come back for another shot. Or the race will come down to Gingrich vs. Romney -- if Gingrich can avoid a fall of his own.

Byron York

Byron York, chief political correspondent for The Washington Examiner