FILE - In this Aug. 16, 2018, file photo, Montana Gov. Steve Bullock walks down the main concourse during a visit to the Iowa State Fair in Des Moines, Iowa. Former Vice President Joe Biden and several nationally known senators are commanding most of the attention in Democrats' early presidential angling, but there are several governors and mayors, including Bullock, eyeing 2020 campaigns, as well. (AP Photo/Charlie Neibergall, File)
CNN  — 

Steve Bullock won the endorsement of Iowa Attorney General Tom Miller on Thursday, the governor’s campaign announced, making the Montana Democrat the first presidential candidate to win the support of an Iowa Democrat elected statewide.

Miller’s endorsement of Bullock is not a surprise. The longtime attorney general has long been a supporter and has quietly boosted the governor’s campaign in Iowa long before Tuesday, when Bullock officially jumped into the race.

“I’m proud to endorse Steve Bullock for President of the United States,” Miller says in a campaign video. “Believe me I know I shouldn’t tell Iowans who to caucus for. But I ask you to go out and hear Steve and meet him and see what you think.”

He adds: “The stakes are so high this time around. It’s up to us to get it right.”

In a statement about his endorsement, Miller – who is serving his 10th four-year term as attorney general, making him the longest serving attorney general in the nation – describes Bullock as someone “with proven character, a record of success, and an ability to connect with all Americans.”

Bullock thanked Miller for his support in a statement, adding that it will be “a personal joy to campaign alongside Attorney General Miller throughout the Caucus.”

“I look forward to taking our shared value of fighting for the rights of every American across Iowa and the country,” he said.

On Thursday, Bullock said on CNN’s “New Day” that he was “pleased” by Miller’s endorsement.

“I think he was the first person outside of Illinois to endorse Barack Obama and he’s the first statewide official to endorse in the entire field – (I) was pleased that he has the trust in me that he thinks I can get this done,” he said.

Bullock announced his campaign on Tuesday in Helena, Montana, outlining a campaign against politics in Washington and partisanship. Bullock plans to run as a progressive who has a proven track record in a state that President Donald Trump won by more than 20 percentage points in 2016, the same year the governor won re-election.

And that strategy means his campaign believes the governor has a better shot in Iowa – another state that went to Trump in 2016 – than other Democrats.

Asked by CNN on Wednesday, Bullock said he looks “forward to actually spend a lot of my time in Iowa.”

“I do think that I need to do well in Iowa,” Bullock said. “I think everyone in the field needs to do well in Iowa.”

Miller is a key part of that plan. He is popular among Democrats in the state and, according to Galia Slayen, the attorney general will officially endorse Bullock at an event in Des Moines on Thursday and then travel the state with the governor on his three-day, eight country tour of the state.

CNN’s Devan Cole contributed to this report.