SPRINGFIELD — Although the governor's race will be in the spotlight throughout the upcoming election season, several primary election battles are on tap for seats in the General Assembly and U.S. Congress.

Monday marked the deadline to submit paperwork to get on the March primary election ballot.

In all, more than 540 candidates for state and local offices submitted nominating petitions in the week-long filing period.

Following is a rundown of some of the looming races:

12th CONGRESS: Freshman U.S. Rep. Bill Enyart, a Democrat from Belleville, is unopposed in the primary election but will face challenges from Republican state Rep. Mike Bost of Murphysboro and Green Party candidate Paula Bradshaw of Carbondale.

Bost is leaving the General Assembly after 18 years in Springfield. Bradshaw ran unsuccessfully for the seat in 2012.

13th CONGRESS: Voters in both parties will see crowded primary races in the fight over this central Illinois congressional district.

On the Republican side, incumbent U.S. Rep. Rodney Davis of Taylorville is being challenged by Urbana attorney Erika Harold and Michael Firsching of Moro.

On the Democratic side, former Madison County Judge Ann Callis of Edwardsville has the financial backing of the Democratic Congressional Campaign Committee. But Champaign residents George Gollin and David Green have filed to challenge her.

In addition, Bill Byrnes, a school bus driver for the Normal-based Unit 5 school district filed to run. The 66-year-old Byrnes said he won't have much money but thinks he can do a better job representing voters who are "angry and disheartened."

"They want people who want to work and who will work together," said Byrnes, a former Roscoe resident who resides in Bloomington.

16th CONGRESS: Republican U.S. Rep. Adam Kinzinger of Channahon faces a primary challenge from Rockford Tea Party leader David Hale. Hale said he got on the ballot because voters told him that Kinzinger, a military pilot and former McLean County board member, needs to be challenged.

"We did this because we want to tell Washington there is a choice," Hale said.

Filing on the Democratic side is Randall Wayne Olsen of Ottawa.

18th CONGRESS: Two Democrats have filed to take on Republican U.S. Rep. Aaron Schock of Peoria. Rob Mellon of Quincy and Darrel Miller of Danvers will meet in the March primary, with the winner running against Schock in the November general election.

Mellon is a history teacher in Quincy and has sought to run for the seat in 2006. Miller made an unsuccessful bid for the seat in 2012.

96th HOUSE DISTRICT: Democratic voters will have a choice in March between keeping freshman state Rep. Sue Scherer of Decatur or picking a new candidate to run for the office in Gina Lathan of Springfield. Mike Bell of Edinburg and Landon Laubhan of Springfield are vying for Republican support.

102nd HOUSE DISTRICT: State Rep. Adam Brown of Champaign could face a challenge in November. On Monday, Democrat Matt Forcum of Mode filed to run against the Republican in the general election.

106th HOUSE DISTRICT: State Rep. Josh Harms of Watseka could face a challenge in November. On Monday, Democrat William Nutter of Watseka filed to challenge the freshman Republican.

110th HOUSE DISTRICT: A three-way Republican primary is shaping up in the district currently represented by state Rep. Brad Halbrook, R-Charleston. Coles County Sheriff Darrell Cox of Ashmore, Kevin Garner of Hazel Dell and Reggie Phillips of Charleston are vying for the GOP nomination in the eastern Illinois district. No Democrats filed to run in the district. Halbrook is vacating the seat after one term.

115th HOUSE DISTRICT: State Rep. Mike Bost's decision to run for Congress after a lengthy tenure in Springfield has triggered primary races for his seat in the Illinois House on both sides of the aisle.

Terri Bryant of Murphysboro and Robert "Bob" White of Mount Vernon filed to run for the GOP nomination in the southern Illinois district.

On the Democratic side, William "Bill" Kilquist of Carbondale and Tony Mayville of DuBois filed for a spot on the ballot.