On eve of Iowa Caucus, Obama most vulnerable president yet in Gallup polling?

From the Examiner:

The night before the January 3rd Iowa Caucus and commencement of Republican Party primary voting to determine the GOP 2012 nomination, Gallup job approval data suggests Barack Obama finished his third year in office as arguably the most vulnerable elected presidential incumbent championed by either party in fifty-five years.

Obama outscored only Jimmy Carter in November...

Gallup maintained that..., if Obama's numbers do not "increase significantly this month, he will be the first elected president in Gallup records to be below 50% in December of his third year in office.”...

The most recent data posted ahead of the Iowa Caucus showed Gallup’s December 27th – 29th three-day rolling average for Barack Obama’s job performance rating at 43% approval and 48% disapproval...