A top political handicapper has changed its prediction for the November Senate election in Montana to show an advantage for Republicans as Democratic Sen. Jon Tester has begun to slip in polling.
The battle between Tester and Republican Senate candidate Tim Sheehy, a former Navy SEAL, was shifted from a "toss up" to "leans Republican" by Sabato's Crystal Ball at the University of Virginia's Center for Politics on Friday, with less than nine weeks until the election.
The rating change followed the Thursday release of a new AARP poll showing Sheehy with a six-point 51%-45% advantage over Tester in a two-way race. In an expanded field, Sheehy still defeated Tester 49%-41%.
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"Beyond the polling, history and recent trends are just not on Tester’s side, as we have mentioned previously," wrote managing editor Kyle Kondik. "He is one of a relatively small number of partisan outliers in either chamber of Congress, holding a Senate seat that the other party won by 16 points in the most recent presidential election."
"Perhaps ticket-splitting returns in force this year — if it did, Tester could still survive. But the longer-term trend is clearly toward less ticket-splitting," he said.
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Campaigns for Tester and Sheehy did not immediately provide comment to Fox News Digital.
Montanans first elected Tester to the Senate in 2006, and he's won re-election twice, despite the state traditionally voting Republican.
The Democratic senator's re-election bid in 2018 did not coincide with a presidential election, freeing him from concerns that the Democrat presidential nominee would influence his race. But now, Vice President Kamala Harris will be at the top of the Democratic ticket, while former President Trump, who won Montana twice in 2016 and 2020, will lead the Republican ticket in the state.
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Tester has held off endorsing Harris and did not attend the Democratic National Convention last month. Despite appearing to distance himself from Harris and his party, the strategy's effectiveness is unclear, particularly as reports have indicated that Tester, who was leading the Democratic Senatorial Campaign Committee (DSCC) at the time, was personally responsible for recruiting Harris for the Senate in 2015.
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In addition, the Montana Democrat offered a ringing endorsement of fellow senator Harris when she was chosen as President Biden's running mate in 2020. He wrote on X, "My friend @KamalaHarris is a proven fighter and an excellent pick for Vice President. As VP, I'm confident she will continue to fight for working families across this country. Looking forward to supporting her and @JoeBiden in November."
More recently, Tester claimed, "I’m not going to endorse for the presidential – and I will tell you why."
"Two reasons: No. 1, I’m focused on my race. And No. 2, folks have wanted to nationalize this race, and this isn’t about national politics. This is about Montana," he said, justifying his decision not to offer his seal of approval to Harris.
Fox News Digital's Aubrie Spady contributed to this report.