Primary election season is winding down this week with some closely watched primaries in the following key states: Florida, Arizona, Vermont and Oklahoma. Here's a look at what's happening and which contests will be the most interesting this election cycle.

Florida

Although Florida is as much of a red state as you can imagine, the state's Democratic primary is an important one for Republican-turned-Democrat Charlie Crist. He wants to take on incumbent Republican Gov. Rick Scott in November, but has to make it out of his new party's primary first. The thing working against him is that he recently switched his political allegiance which could lead some voters to look at him with a bit of scepticism. Crist, according to reports, has to soundly beat Nan Rich who is running as the "real Democrat" contender in that party's primary explains ABC News.

Arizona

With term limits keeping Gov. Jan Brewer from running again it's a face-off for her eventual successors, and only one of the candidates has her official support. Plus, it's an open governors race that pits tough border security candidates against each other. However, it also puts top candidates, such as the Tea Party supported Doug Ducey, the state's treasurer, against Republican Scott Smith, who has the backing of the former governor Brewer.

Vermont

A write-in candidate with some heavy GOP backing could unseat Gov. Peter Shumlin, a two-term incumbent Democratic in the heavily Democratic state. The Republican primary in Vermont will pit Dan Feliciano, the write-in candidate and a Libertarian against GOP stalwart Scott Milne, Steve Berry and Independent Emily Peyton.

Oklahoma

The run-off election for the state's 5th District will see former senator Steve Russell (a pivotal leader and former Army official who helped capture Sadaam Hussein) and Patrice Douglas take on Rep. James Lankford whose win in June failed to meet the right percentage of votes to make it all the way to November.