Since I've commented quite a bit on polling that as I read it shows Mitt Romney broadly acceptable to most Republican voters, I definitely need to say something about a new poll today that doesn't exactly show that. Gallup got around to actually asking that very question ("Please tell me if you would find ___ to be an acceptable nominee for president from the Republican Party, or not"). The answers mostly showed the weakness of the field, with six of the eight candidates asked about scoring well below 50% acceptable. But the clear most-acceptable candidate is Newt Gingrich, with a 62/34 acceptable/not acceptable ratio, while Romney is only at 54/41.
There are a lot of ways to look at this, but overall it's certainly a piece of evidence that the anti-Romney vote is, well, around 40%. Only a piece of evidence, however. It's not clear how hard these kinds of numbers might be, in either direction. On the positive side, it seems unlikely that Newt would remain over 60% once more Republicans know that he's been lobbying for Freddie Mac, and supported the individual mandate on health insurance, and made a climate change ad with Nancy Pelosi, and all the rest of it. On the other hand, it's certainly possible that the "unacceptable" answers are awful soft, for Romney and for everyone else.
In particular, as Greg pointed out, Romney only does three points better on the "acceptable" scale with moderate Republicans than does Newt. This isn't the first indication we've had that Romney isn't doing as well with moderate Republicans as one would think he should be. Whether that means he has some room to grow or that he's just not an appealing politician is, I guess, still entirely up in the air at this point.
I still overall don't see a low cap on Romney's support, but of course all the evidence counts, and polling in general begins to be a little more important the closer we get to actual voting. I'll be continuing to track anything more we get on this one.