Former House Speaker Newt Gingrich’s rise (again) in the presidential race has been as meteoric as it has been surprising.

Nothing captures that ascent as well as Gallup’s latest tracking poll, which, when viewed from even a slight distance, captures the new normal of the presidential race.

The orange line below tracks Gingrich’s standing in the Gallup poll since early November. The black line represents the poll numbers of former Massachusetts governor Mitt Romney.

What do the Gallup national numbers tell us? That national polling — at this point in the primary race, at least — is essentially a gauge to track momentum/buzz/conventional wisdom. (For much more on Gingrich’s national polling surge, check out “Behind the Numbers” — the Post’s polling blog.)

In the wake of his New Hampshire victory, Romney’s national lead stretched to its largest margin of the entire race as all of the chatter in the race centered on the idea that he was the all-but-certain nominee.

Gingrich’s performances in two debates last week coupled with his sweeping victory in South Carolina has shot his poll numbers skyward over the past five days or so.

While the chart above has to hearten Gingrich supporters — and help the candidate raise much-needed money — the volatility of the national electorate should temper any undue exuberance.

After all, one week you’re Mitt Romney. The next, you’re, well, Mitt Romney.