Tonight’s GOP contests — primaries in Alabama and Mississippi and a caucus in Hawaii — have the potential to really shake up the race. The two Southern primaries in particular could potentially make or break some campaigns.

We will be tracking the results tonight at Firedoglake.  Polls close in Alabama and Mississippi at 8 pm Eastern. The Hawaii Caucus runs until 8 pm local time, which is 2 am Eastern.

There has been relatively little recent polling of Alabama and Mississippi, but the polling that has taken place shows the top three candidates extremely close in both states. In Alabama PPP found Mitt Romney 31%, Newt Gingrich 30%, Rick Santorum 29% and Ron Paul 8%. In Mississippi PPP found Gingrich 33%, Romney 31%, Rick Santorum 27% and Ron Paul 7%.   So it’s conceivable that any of the three top candidates could win either or both these states tonight.

A double win by Romney in the South, where he has struggled, would likely create the impression that the primary is completely over. A double win for Gingrich would give him the justification and boost needed to continue his run. A double win for Santorum could potentially push Gingrich out of the race and allow Santorum to finally get the head to head fight with Romney he’s been seeking.

Both Santorum and Gingrich probably need wins tonight.  But for Romney, simply having Gingrich do well enough to keep running and splitting the very conservative vote would be a decent outcome. Winning a plurality in the South would help Romney end this primary quickly, but Romney doesn’t technically need to win the South to get the nomination, thanks to his strengths elsewhere.

In Hawaii I’m not aware of any polling as far, but I predict Romney should be a strong favorite to win there. Romney has the larger and better operation, which tends to help in states that receive less attention. Most importantly, Hawaii has a surprisingly large Mormon population. Roughly 5% of the state are members of the LDS. Mormons have been voting strongly for Romney, and so far Romney has won every state where Mormons make up 4% or more of the population. If the pattern holds up Romney should win Hawaii by a healthy margin.

I will be live blogging the results from Alabama and Mississippi on the FDL main page tonight.