Newt’s easy. While all of us on the Democratic side were playing “root for Newt,” Republicans were taking the proverbial second and third look — and getting scared by what they saw. Hello, Herman Cain.

Oldest rule in politics: The faster the balloon fills with air the faster it blows up. On the one hand, everyone knew Newt Gingrich had baggage. Everyone knew he could be, well, erratic, and that he had a lot of “nutty” ideas (colonizing Mars). But there was a moment there, maybe a week or two, when compared to the bore from Boston he was a breath of authentic fresh air.

And then it hit. The night his second wife, Marianne Gingrich, went on television to talk about his affair in her bed and his request for an open marriage, he successfully deflected the issue by attacking the press. It worked long enough for him to win South Carolina. Women held firm.

And then it turned out that maybe ABC had not declined his campaign’s offer of other guests, and women started thinking about just how tacky it was (it was the bed stuff, never really denied, that got to a lot of women), and there was a bad debate in which Mitt Romney actually came out swinging, and all of a sudden Newt had to defend his continued presence in the race.

Romney has it, the media declared. Any smart money left jumped on the train before it left the station. Romney went back to attacking Obama. There was much talk of how the fat lady was tuning up.

Not so fast. In roared Rick Santorum, the Iowa winner who hadn’t won anything since, to a three-for-three night that included two states Romney actually won in 2008, when he was losing the nomination to John McCain.

Can Santorum beat Romney? Not likely. After his first moment in the sun, he faced a string of defeats. Now that he’s had his second moment, the spotlight will return. Darwin? Not so fast. On many issues, Santorum makes Gingrich look like a sage. And then what? Back to Gingrich? A moment for Ron Paul?

What’s interesting about the Republican process so far is not so much who gets to be the unRomney every week, but the problems Romney himself is having locking up this race despite the fact that everyone in the media and the party establishment has declared it over. What is the matter with these voters? Haven’t they heard?

Of course they have. But plainly, they’re not happy. They’re not ready to make Romney the king. Told repeatedly that he is the most electable of the bunch, as he almost certainly is, and that the sooner it’s over the better off he will be (maybe), they’re just not drinking the Kool-Aid.

If you ask me, it’s not about Santorum or Gingrich, or Paul if he’s next. This is all about Romney. This is all about the activists (they are the people who go to caucuses and vote in beauty contests, which is what Missouri was) not being ready to sign on the dotted line. Maybe they think ABR (Anybody But Romney) still has a chance. Or maybe they think the only way to keep Romney from returning to his more moderate Massachusetts roots is to keep the contest going and ensure that there will be members of the platform committee and delegates to the convention who are not taking orders from the Bay State brigade.

Either way, it’s an issue for Mitt. The question is no longer whether Gingrich can win, or Santorum; the question is why can’t Mitt lock it up. If it really is his, why are the voters refusing to give him the victories he needs. To put it bluntly: What’s wrong with Mitt?

With weeks to go before the next big contests, that’s the only thing to talk about. OK, he’s boring and scripted. He’s Mormon, and Mormons aren’t flocking to him. He’s rich and corporate and doesn’t pay as high of a percentage of taxes as a lot of working stiffs do. None of that is good.

But the most likely diagnosis is the obvious one: Conservatives aren’t certain he’s conservative enough. And if there’s a halfway credible alternative, they’re willing to take a chance. That means Mitt has no choice but to veer right (which will make it even harder for him to veer back to the middle after the convention) and go on the attack against his fellow Republicans (which will lead them to attack him, taking away his chance to focus on Obama).

All in all, pretty good viewing. Mitt may be boring, but to most people’s surprise, this contest is shaping up to be anything but.