U.S. Rep. Mark Green, a physician and Army veteran who ascended from the Tennessee statehouse to Washington in January, is taking himself out of the running to be Tennessee's next U.S. Senator.

After months of speculation over whether he would do so, Green, a Republican from Clarksville who is closely aligned with President Donald Trump, announced Thursday that he will stay out of the race to replace current U.S. Sen. Lamar Alexander.

"Over the past several months, I’ve been honored and humbled by everyone asking me to run for the U.S. Senate," Green said in a statement. "As Camie and I have prayed about how to best use our time and resources, I do not plan to seek election to the U.S. Senate in 2020."

Instead, Green said he will focus on helping re-elect Trump and win back GOP control of the House.

"I am looking forward to continuing to represent the people of Tennessee by defending the Constitution and supporting the President, stopping abortion and protecting religious freedom, helping President Trump build the wall and end illegal immigration, standing with our troops and supporting our veterans, and stopping the threat of socialism from destroying America," he said.

Green’s announcement came just hours after former Gov. Bill Haslam, who for months had said he was weighing a bid for Senate, confirmed that he would not be running.

Green, 54, now represents Tennessee’s 7th Congressional district, a position last held by current U.S. Sen. Marsha Blackburn.

Manny Sethi, who, like Green, is also a medical doctor, was the first Republican to jump into the race. Sethi announced in early June that he would run. Democrat James Mackler is the only other top-tier contender for the seat, Tennessee’s only statewide election in 2020.

U.S. Ambassador to Japan Bill Hagerty is considering a bid for the Republican nomination.

In many ways, Green's exit from the race comes as a surprise. With a conservative pedigree that includes opposing Medicaid expansion and supporting Trump, he has ascended the political ladder since first entering politics less than a decade ago.

Green was elected to the state Senate in 2012 and briefly entered the 2018 governor's race only to halt his bid when he was under consideration to be Trump's Army secretary.

While in office, Green has faced criticism for various remarks he's made ranging from Muslims and the LGBTQ community to vaccines.

He told constituents at a town hall meeting in Franklin late last year that he would “stand on the CDC’s desk and get the real data on vaccines,” eventually leading to a complaint being filed against him with the Tennessee Department of Health.

In June, a spokesman for Green dismissed the complaint as frivolous, clarifying that Green had since looked at the most recent data available and now believes “it is clear that there is no link” between vaccines and autism.

While in the Army, Green was a medic for the Operation Red Dawn team that carried out the capture of Saddam Hussein in 2003. Green went on to write “A Night with Saddam,” a book about his six-hour interview with Hussein the night of his apprehension.

Green received the Bronze Star, Meritorious Service Medal, Achievement Medal and various other awards for his time in combat. His military career spanned 20 years, from 1986 to 2006.

Green moved to Tennessee in 2002 after growing up in Mississippi. He is married to Camie Green and has two children.

Since January, Green has missed 92 of the House’s 433 roll call votes, 21 percent of them. That’s significantly higher than fellow freshman Tennessee congressmen Tim Burchett, who has missed five, and John Rose, who missed three votes.

Reach Natalie Allison at nallison@tennessean.com. Follow her on Twitter at @natalie_allison.

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