BISMARCK, N.D. (AP) — North Dakota Republican Gov. Doug Burgum announced Monday that he will not seek a third term as governor, over a month after he ended his bid for the GOP presidential nomination.

His recent endorsement of former President Donald Trump, and Trump’s praise of the little-known governor, have fueled speculation about Burgum serving in a possible second Trump administration.

Burgum, 67, is a wealthy software entrepreneur who won an upset victory in 2016 over the state’s popular attorney general in the Republican gubernatorial primary election. He campaigned on a message of “reinventing” state government amid a $1 billion state revenue shortfall. He went on to win his first term and reelection in 2020 by overwhelming margins.

“Serving as governor and first lady of the great state of North Dakota has been one of the most incredible and rewarding experiences of our lives,” Burgum said in a statement Monday. “Kathryn and I are eternally grateful to the citizens of North Dakota for twice giving us this opportunity to serve the state we love so much.”

His decision creates an open race for the state government’s top job in the sparsely populated, Republican-dominant state. Republicans hold every statewide and congressional seat and control the Legislature with supermajorities. Democrats last won the governor’s office in 1988, and haven’t won a statewide election since Heidi Heitkamp’s U.S. Senate victory in 2012.

Burgum entered office at the height of the Dakota Access oil pipeline protests. He led the state’s response to the coronavirus pandemic with messages of staying “North Dakota smart” and urging “personal responsibility” as COVID-19 cases soared. He’s also had to deal with terrible droughts, crippling winter storms and important questions of how to spend the state’s federal coronavirus aid and how to use the state’s ballooning oil tax savings.

As governor, Burgum championed a Theodore Roosevelt presidential library in the state’s colorful Badlands where the 26th president hunted and ranched in the 1880s. He and his wife Kathryn, a recovering alcoholic, prioritized recovery from addiction as a top issue in his administration.

He’s pushed income tax cuts with mixed results. He signed a sheaf of bills last year opponents decried as harmful to transgender people, including a ban on gender-affirming care for children and restrictions on school athletic participation.

His relationship with lawmakers has been rocky. In 2020 and 2022, Burgum targeted the seats of fellow Republicans with millions of his own money, including the top House budget writer.

Burgum supported a term limits ballot initiative in 2022. The governor cannot be elected more than twice, and state lawmakers are limited to eight years in the House and eight years in the Senate. The term limits are not retroactive and do not prevent Burgum from running for a third or fourth term.

Burgum poured over $12 million of his own money into his presidential campaign, which he ended in December after six months. He drew attention for giving $20 gift cards to donors in order to meet donation requirements for the debate stage, and criticized debate qualification criteria as arbitrary.

Before becoming governor, Burgum was best known as a software executive. He led Great Plains Software through its acquisition by Microsoft in 2001 for over $1 billion. He was a Microsoft executive until 2007, and has led other companies in real estate development and venture capital.

Burgum is scheduled to give his State of the State address Tuesday. North Dakota’s Legislature is not in session this year, but Burgum has made the speech a yearly tradition in a different town each time, whereas his predecessors typically gave it only at the start of the biennial legislative session in Bismarck.