State: Alabama
Type of election: Primary
How it works: 47 delegates are up for grabs. 26 are given proportionally according to statewide results, the remaining 21 are given out at the congressional district level. If any candidate gets more than 50 percent, the delegates are given out winner-take-all. The primary is open.
Official election results: Alabama Secretary of State
Republican candidates: Newt Gingrich, Ron Paul, Mitt Romney and Rick Santorum (all others have dropped out or are polling at less than 1 percent)
Democratic candidates: There is no Democratic primary.
Previous performance: In 2008, Romney finished third to Mike Huckabee with nearly 18 percent. Paul finished fourth with less than 3 percent. Obama won the Democratic primary with 56 percent.
Newspapers: Birmingham News, full list
Television stations: Full list
Progressive blogs: Left in Alabama
Latest polling: New York Times:
Nate Silver gives Gingrich a 48 percent chance of winning, followed by Romney at 39 percent, and Santorum at 13.
Bottom line: Those are the most competitive numbers we've seen yet from Silver and it appears like this one is going down to the wire. A win by Romney would help him get over his "can't win in the South" concerns and could give him a big boost. A loss for Gingrich is disastrous.
State: Mississippi
Type of election: Primary
How it works: 37 delegates are up for grabs. 25 are awarded proportionately according to the statewide results and the other 12 are awarded by congressional district.
Official election results: Mississippi Secretary of State
Republican candidates: Newt Gingrich, Ron Paul, Mitt Romney and Rick Santorum (all others have dropped out or are polling at less than 1 percent)
Democratic candidates: There is no Democratic primary.
Previous performance: In 2008, Romney finished fourth in the primary, despite having dropped out of the race, getting 1.5 percent of the vote. Paul finished third with just under four percent. Obama won the Democratic primary with over 61 percent.
Newspapers: Jackson Clarion-Ledger, full list
Television stations: Full list
Progressive blogs: A Liberal in the Midst
Latest polling: New York Times
Nate Silver also rates Mississippi as very competitive, giving Romney a 53 percent chance, Gingrich 45 percent and Santorum 2 percent.
Bottom line: A sweep of the Southern states would put Romney in very good position and losses by Gingrich would hurt him quite a bit. Santorum appears to be fading and Paul is as irrelevant as ever.