State Auditor Matt Rosendale won the GOP nomination Tuesday night to take on Montana Democratic Sen. Jon Tester in November. 

With 96 percent of precincts reporting, Rosendale led a four-way field with 34 percent of the vote, according to The Associated Press. Former district judge Russ Fagg was in second place with 29 percent. Fagg ran with the support of many former Montana elected officials, including ex-Reps. Rick Hill and Denny Rehberg and three former governors.

Tester ran unopposed in the Democratic primary.

Rosendale will now try to unseat the incumbent, who’s never won more than 50 percent of the vote, in a state that President Donald Trump won by more than 20 points in 2016. 

Tester starts with a significant financial advantage. He ended the pre-primary reporting period with $6.4 million in the bank compared to Rosendale’s $392,000. Inside Elections with Nathan L. Gonzales rates the race Tilts Democratic.

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It’ll be a contest between two flattops: Tester made his signature coif the subject of an ad during his first Senate run in 2006. Rosendale shot a similar spot for his debut Senate ad this spring.

As a statewide elected official, Rosendale began the GOP race with higher name recognition. He was ahead for much of the primary, but what little polling was released was conducted by his campaign or for outside groups backing him. 

The Club for Growth’s political arm spent about $1.7 million boosting Rosendale and attacking Fagg. Two outside groups funded by GOP megadonor Richard Uihlein also supported Rosendale, who was endorsed by conservative senators such as Ted Cruz of Texas and Rand Paul of Kentucky. 

Rosendale became the party’s top pick after other statewide elected officials passed on the race. He is one the rare GOP Senate candidates who enjoyed early support from both establishment Republican forces in Washington and anti-establishment interests such as the pro-Trump outside group Great America Alliance and former Trump adviser Steve Bannon.

Rosendale had suggested he’d back Mitch McConnell to remain as majority leader leader, but he was at odds with the National Republican Senatorial Committee late last year when he praised the public service of Alabama Senate candidate Roy Moore after the NRSC had already cut ties with him. 

Despite being an elected official, Rosendale tried to run as a conservative outsider in the Senate primary. He was a real estate developer in Maryland until 2002, when he moved to Montana. His defenders have responded to carpetbagging charges by arguing that he was settled in the state for a while before running for office. Rosendale was elected to the state House in 2010 and then the state Senate two years later.

When Rosendale ran for Congress in 2014, he finished third in the GOP primary for the at-large House seat eventually won by Ryan Zinke, the current Interior secretary. Rosendale’s Maryland roots came under attack in that race, when critics seized on his Baltimore accent. 

His opponents in this year’s Senate primary used the outside spending on his behalf to argue that he was beholden to out-of-state special interests. Fagg, in particular, used Rosendale’s out-of-state origins to play up his own identity as a “fourth-generation Montanan.”

The state Democratic Party has already tarred Rosendale as “Maryland Matt,” a moniker that a super PAC called Principles First PAC used in TV advertising against him in the primary, too.

State Democrats also seized on a report from Talking Points Memo last week that said Rosendale, despite identifying himself foremost as a rancher, has never owned any cattle.

That came after revelations that his signature appeared on two forms that had boxes checked indicating he was a Maryland resident in 2015.  The forms were related to the sale of a 25-acre property there. Rosendale’s accountant later told the Helena Independent Record that checking the boxes was the title company’s fault, which the company confirmed to Rosendale.

Democrats have signaled they’ll continue to make Rosendale’s Maryland roots a central part of their message against him heading into the general election. 

As soon as the race had been called for Rosendale, Tester’s campaign challenged the GOP nominee to participate in a June 17 debate, calling him “Maryland Matt.” 

“The choice for Montanans this November couldn’t be more clear. Jon Tester is a third generation Montanan who still farms the land homesteaded by his grandparents,”campaign manager Christie Roberts said in a statement.

“Matt Rosendale is an East Coast developer who looks out for himself,” she added.

On Wednesday, the Democratic super PAC American Bridge 21st Century released a digital ad targeted to GOP voters on social media that uses Fagg’s criticism of Rosendale’s roots against him. 

The Montana Senate race started attracting outside spending well before the general election matchup was set. Trump called for Tester’s resignation after the two-term senator raised concerns about the president’s nominee for Veterans Affairs secretary. The dispute led to a barrage of ads from Tester’s opponents and allies. 

Republicans are trying to tie Tester, a former chairman of the Democratic Senatorial Campaign Committee, to Washington, arguing that he’s not the same working farmer that he used to be.

“The Battle of the Flat-Tops has finally begun and I have no doubt the people of Montana are going to send Jon Tester packing because he has become just another politician who makes empty promises, obstructs President Trump’s agenda, and doesn’t uphold our Montana values,” Rosendale said in his victory statement.