Governor Kemp will not be a candidate for Senate in Georgia next year, dashing GOP hopes of beating Senator Ossoff and expanding their majority. Mr. Kemp is the only Republican who was beating Mr. Ossoff in recent public polls. 

Despite months of wooing from President Trump and Senate Republican leadership, Mr. Kemp made the announcement on Monday that he would not be a candidate and would instead complete his term as governor before leaving office in 2027. 

“I have had many conversations with friends, supporters, and leaders across the country who encouraged me to run for the US Senate in 2026,” Mr. Kemp said in a statement. “After those discussions, I have decided that being on the ballot next year is not the right decision for me and my family.”

“I spoke with President Trump and Senate leadership earlier today and expressed my commitment to work alongside them to ensure we have a strong Republican nominee who can win next November, and ultimately be a conservative voice in the US Senate who will put hardworking Georgians first. I am confident we will be united in that important effort,” he added. 

Georgia, which Mr. Trump won in 2024, is the only state with a Democratic senator running for re-election next year. Beyond Mr. Ossoff, Democrats will have to defend seats in Michigan, New Hampshire, Minnesota, and Virginia just to keep their current 47-seat minority. In order to take the upper chamber, they would have to run the table by flipping states like Maine, North Carolina, Texas, and Ohio. 

Based on the polling in Georgia, Mr. Kemp was the Republican candidate who by far was best positioned to flip the seat to the GOP. According to one April survey from the Atlanta Journal-Constitution, Mr. Kemp led Mr. Ossoff — 49 percent to 46 percent — in a hypothetical matchup. Mr. Ossoff beat all other potential GOP rivals, according to the poll. 

Mr. Ossoff led the secretary of state, Brad Raffensperger, by nine points, the insurance commissioner, John King, by 13 points, and Congresswoman Marjorie Taylor Greene by 17 points in the general election, according to the AJC survey. 

Ms. Greene has been hinting at a run for months, though has cautioned that she likely would not be a Senate candidate should Mr. Kemp enter the race. With her governor stepping aside, Ms. Greene would be the overwhelming favorite to win the Republican nomination next year. 

One poll from the Trafalgar Group in April found that Ms. Greene would win 43 percent of the vote in the Republican primary if she were to run. Her closest competitor would be Mr. Raffensperger, at 22 percent. Three congressmen, Mike Collins, Rich McCormick, and Buddy Carter, would all win less than 15 percent, according to the poll.