Republican Tim Sheehy won Montana's Senate race on Wednesday, denying Democratic incumbent Jon Tester a fourth term and strengthening Republicans in an upper chamber they will control along with Donald Trump in the White House.

This closely watched race was also seen as a referendum on whether Democrats can win in predominantly rural states that have turned to Donald Trump's far-right Republicanism.

The race raised questions about whether grassroots campaigns — which have proven successful in Montana in the past — are even effective when news coverage and campaign spending have made local politics national.

Montana, which has a population of 1.1 million, spent $280 million on campaign advertising, according to the Associated Press. Pennsylvania and Ohio, where $340 million and about $500 million were spent respectively, have about 10 times the population of the western state, further underscoring its perceived importance to both political parties.

Tester, 68, reiterated his Montana roots and rural childhood during his campaign, often talking about the three missing fingers on his left hand, lost in a meat grinding accident; The tester remains the owner of the device.

Tester has been a senator in Montana for 18 years. Voters have praised his advocacy for farmers, military veterans and Native Americans. Before the election, however, Tester was trailing Sheehy in opinion polls.

Sheehy, 37, is a former Navy Seal who moved to Montana in 2014 to start an aerial firefighting business and raise a family. Like Trump, he had no political experience before this campaign and is hostile to the press. Sheehy has also faced controversy related to misleading statements about his past financial problems.

Sheehy said in a statement that he has served the country since he was 18 and that he was honored to be elected to the Senate.

“Since day one, we've been running a grassroots campaign, talking directly to Montanans about how to make Montana affordable again, make America strong again and bring back Montana's common sense, which means a secure border, safe roads, cheap gas. “Cops are good, criminals are bad, boys are boys and girls are girls,” he said.

While Tester narrowly won his previous three Senate bids, Trump's candidacy posed a risk he had not previously seen. Montana's politics have become more conservative and he faced an uphill battle with Trump at the top.

When Tester became a senator in 2007, nearly every elected office statewide was held by a Democrat. As Republicans have gained ground — Tester is the only remaining Democrat in statewide elected office — he has distanced himself from Harris.

Tester did not support Kamala Harris. Sheehy, however, enjoys Trump's popularity among Montana residents; He stood by his side at an August rally in Bozeman.

“The Republicans have totally tried to nationalize this race. At every opportunity when they say “Tester,” they say “Biden” or “Harris.” They want to associate him with the national Democrats, and that's what Tester definitely doesn't want to do,” said Mike Dennison, a longtime political analyst and journalist.

“Republicans want to say this race is about control of the Senate. Tester doesn't want to talk about it at all. He wants to talk about himself and his problems. That’s what’s going on here: Democrats have had a hard time in rural America, and Montana is certainly rural America.”

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