First, here's the polling trends for the remaining GOP aspirants nationwide.
As you can see, Gingrich's rapid ascent has clearly halted and begun an equally precipitous drop. The inflection point in his national numbers came right about the beginning of December.
Now let's look at the situation in Iowa.
Again, a similar story. A rapid Gingrich ascent peaking at the beginning of December by a rapid descent. The fall off isn't quite as steep as nationally. But the basic pattern is very consistent.
This should not be terribly surprising. Romney, Paul and Perry are each running a blizzard of negative ads against Gingrich in the state. The AP reported today that pro-Romney 3rd party groups alone are outspending Gingrich by a factor of 8 to 1.
Another point to note is that in the national data Gingrich is falling without a clear rise in the rest of the candidates' numbers. But Iowa looks different. In Iowa all the other candidates except Romney began trending up at or about the same time Gingrich peaked. Ron Paul is in second place according to the TPM Poll Average and rising rapidly.
Finally, let's look at New Hampshire which comes one week after Iowa on January 10th.
Again, the charts shows the trend and in this case I've removed all the candidates besides Romney, Gingrich, Paul and Huntsman. The other contenders are all under 4% and dropping. Here we see the same pivot downward for Gingrich, but Paul and Romney are slipping too. The only candidate with apparent momentum is John Huntsman.
Taken together we have a clear pattern of Gingrich peaking at the beginning of December and then beginning a rapid fall. The key though is that we don't know whether he's going to level off or keep dropping straight into Perry/Cainville. Also important to note, with one exception we don't have any new poll data since December 13th, Tuesday. The exception is that national Gallup tracking poll which goes up to the 16th. And that's where Gingrich's fall is the steepest. If Gallup's numbers are solid and the trend is the same in Iowa, Gingrich could already have fallen out of the lead in the first caucus state.