May marks the true kickoff of primary season for the 2014 elections. While two states, Texas and Illinois, have held March primaries, the real fun begins this month when 11 states hold contests. The races in May include major showdowns between the Tea Party and the GOP establishment, key contests that may help determine control of the Senate and other races that will shape the political battles in the fall.

May 6: North Carolina

The GOP U.S. Senate primary to take on Democratic incumbent Kay Hagan has been ferocious. The three-way contest between State House Speaker Thom Tillis, pastor Mark Harris, and Tea Party activist Greg Brannon has been brutal. While Tillis is favored, he has to get at least 40 percent of the vote to avoid a runoff on July 15. There also are a couple of other interesting races in the Tarheel State, including Clay Aiken’s bid to win the Democratic nomination for Congress in the state’s Second Congressional District.

May 13: Nebraska

The Cornhusker State has what has turned into a major showdown between the Tea Party and the establishment for its open Senate seat. With college president Ben Sasse becoming the Tea Party candidate and former state treasurer and Navy pilot Shane Osborn representing the establishment, this GOP primary in a safe Republican state will be an important litmus test for the mood of conservative voters heading toward 2016.

May 20: Georgia, Idaho, Kentucky, Pennsylvania

The open Senate seat in Georgia has sparked a hard-fought five-way Republican primary between three sitting congressmen, including conservative firebrand Rep. Paul Broun. However, the most recent polls show a likely runoff between longtime congressman Jack Kingston and businessman David Perdue (cousin of the state’s popular former governor, Sonny Perdue), as no candidate is remotely close to the 50 percent needed to avoid a runoff. Whoever wins will face Democrat Michelle Nunn in what is considered one of the more competitive Senate races in November.

In Idaho, close John Boehner ally Rep. Mike Simpson is facing a Tea Party challenge in his Boise-based congressional district from attorney Bryan Smith, who is backed by outside groups like Club For Growth and FreedomWorks. Simpson though has benefited from establishment support, including a television ad starring Mitt Romney.

While Kentucky’s senior senator, Mitch McConnell, looks poised to fend off the strong Tea Party challenge from businessman Matt Bevin in the Bluegrass State, the race is still competitive and McConnell has certainly been greatly weakened for his November matchup against Democrat Allison Lundergan Grimes. A weak showing by the top Senate Republican could be a sign of big electoral problems to come in the fall.

Pennsylvania governor Tom Corbett, a Republican, looks like one of the weakest incumbents in the country and Democrats are ferociously competing for the chance to face him in November. Businessman Tom Wolf is heavily favored against a field that includes State Treasurer Rob McCord and Rep. Allyson Schwartz. There also is a competitive primary for Schwartz’s congressional seat, which features former one-term congresswoman Marjorie Margolies, who may be best known as Chelsea Clinton’s mother-in-law.

May 27: Texas

Texas already held its primary in March but it too features runoff elections and has several notable races where no one broke the 50 percent mark the first time around. Nonagenarian and 34-year veteran of Congress Ralph Hall faces a fierce primary challenge in his northeast Texas district from attorney John Ratcliffe, and in the race for the powerful position of lieutenant governor, Tea Party favorite Dan Patrick is poised to knock off longtime incumbent David Dewhurst.