Six states will hold primaries for Super Tuesday, which could provide major hints about what group will control the Senate come the November elections.

There's plenty to pay attention to for Super Tuesday.

First, there's Kentucky. Senate GOP Leader Mitch McConnell is up against Matt Bevin. McConnell is expected to be nominated again for a sixth term, reports CNN. He is supported by the U.S. Chamber of Commerce, the National Rifle Association and two super PACs from Kentucky. "It was a vintage Mitch McConnell campaign. They found Bevin's weakness and use them against him. They boxed him in and he couldn't move," said Jennifer Duffy, senior editor for the non-partisan Cook Political Report.

In Idaho, Rep. Mike Simpson is up against attorney Bryan Smith, and Simpson appears to be doing pretty well. Smith was endorsed by the Club for Growth, but they stopped spending on his behalf toward the end of the race, reports PBS. Simpson is backed by the U.S. Chamber of Commerce. One of his ads has Mitt Romney saying, "You can take it from me, the conservative choice for Congress is Mike Simpson."

Rep. Bill Shuster faces Art Halvorson in Pennsylvania. Halvorson has accused Shuster of being "one of John Boehner's lieutenants," according to The Washington Post.

The tea party splits votes in Georgia, where Reps. Phil Gingrey, Paul Broun and Jack Kingston and David Perdue are the top candidates. When Sen. Saxby Chambliss said he wouldn't seek re-election, it became a free-for-all. "I think they [Broun and Gingrey] both ran terrible campaigns," said Duffy. "Because both of them were in there, the tea party movement was divided."

In Oregon, Dr. Monica Wehby, a pediatric neurosurgeon, recently earned endorsements from Mitt Romney and Newt Gingrich. Wehby, who supports abortion rights, motivated many anti-abortion groups to spend up to six-figures in opposition of her campaign.