Incumbent Michael Guest (R) defeated Michael Cassidy (R) in the Republican Party primary runoff in Mississippi’s 3rd Congressional District on June 28, 2022. Guest, who has represented this district in Congress since 2019, won with 67.4% of the vote while Cassidy received 32.6%. In the first round of the primary on June 7, Cassidy received 47.5% of the vote to Guest’s 46.9%.

Guest is a member of the U.S. House Homeland Security, Transportation, and Ethics Committees. He served as the district attorney for Rankin and Madison counties in Mississippi before his election to Congress. The Guest campaign highlighted his political experience and what they described as his conservative voting record in Congress. After the June 7 primary, Guest said, “I’ll be working to earn your vote because we need PROVEN, conservative leadership with a real record of fighting for our values—that’s the difference in the runoff election!”

Cassidy is a military veteran who said that he was running for Congress to continue serving his country. After the June 7, 2022, primary, Cassidy said “This is the first step in replacing our current congressman with someone who better represents [our] conservative Mississippi values.” According to Cassidy, “We need more people in Congress that will truly fight for the American people, and Michael Guest is quite simply not equipped for that challenge. He may be a decent man but he has proven to be ineffective at his job, and we need people who know how to fight in Congress.”

Guest voted along with 34 other House Republicans to create a bipartisan commission to investigate the events of January 6, 2021. Cassidy mentioned this vote when he challenged Guest to a debate after the June 7 primary: “I am calling on Mr. Guest to give the voters the opportunity to see us debate and so he can be held accountable for voting for the Democrats’ January 6th Commission.” Guest’s campaign responded saying, “Congressman Guest did not vote for Nancy Pelosi’s Select Committee on January 6th that’s currently in the news…He voted against the Select Committee because he knew it would lead to the witch hunt we are seeing now…[Cassidy] has spent a personal fortune to mislead the people of Mississippi about Congressman Guest’s conservative, Christian character.”

Before the primaries, the Cook Political Report, Sabato’s Crystal Ball, and Inside Elections all rated Mississippi’s 3rd Congressional District as a solid/safe Republican seat.