A new poll in a key Senate battle that may decide if the GOP wins back the chamber's majority indicates the Republican challenger with the edge over the Democratic incumbent.

Republican Senate nominee Tim Sheehy holds a six-point 51%-45% advantage over Democratic Sen. Jon Tester of Montana in an AARP survey released on Thursday in a two-way match up.

And the poll suggests Sheehy leading Tester 49%-41% in a multi-candidate field, with Libertarian Party candidate Sid Daoud at 4% and Green Party candidate Michael Downey polling at 1%. Four percent are undecided.  

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Tim Sheehy, founder and chief executive officer of Bridger Aerospace and US Republican Senate nominee for Montana, at the Bridger hangar in Bozeman, Montana,  on Thursday, Jan. 18, 2024. Photographer: Louise Johns/Bloomberg via Getty Images

Tim Sheehy, founder and chief executive officer of Bridger Aerospace and US Republican Senate nominee for Montana, at the Bridger hangar in Bozeman, Montana,  on Thursday, Jan. 18, 2024. Photographer: Louise Johns/Bloomberg via Getty Images (Louise Johns)

Sheehy, a former Navy SEAL and Purple Heart recipient who served in the wars in Iraq and Afghanistan and who serves as CEO of Bridger Aerospace, a Montana-based aerial firefighting and wildfire surveillance services company, enjoys the backing of former President Trump, who headlined a rally in Montana last month. Trump carried red-state Montana by 16 points over President Biden four years ago.

The poll indicates Trump is ahead of Vice President Kamala Harris, the Democrats' 2024 nominee, by 15 points.

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Sheehy also has a strong ally in Sen. Steve Daines of Montana, the chair of the Senate GOP's campaign committee.

Tester is considered of the most vulnerable Senate Democrats running for re-election this year, and Republicans are heavily targeting the incumbent.

Sen. Jon Tester (D-MT) arrives for a Senate Appropriations Subcommittee on Homeland Security hearing at the U.S. Capitol on April 10, 2024 in Washington. (Photo by Samuel Corum/Getty Images)

Sen. Jon Tester (D-MT) arrives for a Senate Appropriations Subcommittee on Homeland Security hearing at the U.S. Capitol on April 10, 2024 in Washington. (Photo by Samuel Corum/Getty Images) (Samuel Corum)

The poll's release highlights that "with Republicans accounting for 39% of likely voters and Democrats only 24%, Tester will need to boost his edge with Independents or gain among Republicans to pull ahead."

But beating Tester, a Montana farmer and former state lawmaker who's running for a fourth six-year term in the Senate and has a history of winning tough contests, is far from an easy task.

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Democrats control the Senate by a razor-thin 51-49 margin, and Republicans are looking at a favorable election map this year with Democrats defending 23 of the 34 seats up for grabs.

Jon Tester, Tim Sheehy

Sen. Jon Tester and Republican Montana Senate nomineeTim Sheehy. (Kevin Dietsch/Louise Johns)

One of those seats is in West Virginia, a deep red state that Trump carried by nearly 40 points in 2020. With moderate Democrat-turned-Independent Sen. Joe Manchin, a former governor, not seeking re-election, flipping the seat is nearly a sure thing for the GOP.

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And in Ohio, which Trump comfortably carried four years ago, Republicans are aiming to defeat Democratic Sen. Sherrod Brown.

Five more Democratic-held seats are up for grabs this year in crucial presidential-election battleground states.

With Democrats trying to protect their fragile Senate majority, former GOP Gov. Larry Hogan of blue-state Maryland's late entry into the Senate race in February gave them an unexpected headache in a state previously considered safe territory. Hogan left the governor's office at the beginning of 2023 with very positive approval and favorable ratings.

The new AARP survey in Montana was conducted by the bipartisan polling team of Fabrizio Ward (R) & David Binder Research (D). The firms interviewed 1,064 likely voters from August 25-29, with an overall sampling error of plus or minus 3.5 percentage points.

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