The marquee race between Sen. Jon Tester (D-MT) and Republican Tim Sheehy could determine control of the upper chamber of Congress, but the ballot will also feature libertarian candidate Sid Daoud and Barb. The Montana Democratic Party was attempting to have Barb disqualified from the ballot, alleging that because he was “appointed” to replace the Green Party candidate who won the primary but later dropped out rather than “nominated” by the party, he was ineligible to appear on the general election ballot.

A lower state court denied the Montana Democratic Party’s effort to boot Barb, and the state’s high court denied the party’s attempt to get a preliminary injunction to block Barb and denied taking control of the case on Tuesday.

“[The Montana Democratic Party] has not convinced us that the District Court erred in its rulings in its September 3, 2024 Order, although we reach the same result as that court under a different analysis. Since we have not concluded that the District Court is proceeding under a mistake of law, this matter is not susceptible to writ of supervisory control,” the court ruling noted.

Tester is widely considered the most vulnerable Democratic Senate incumbent in an election year in which Democrats are on defense in Senate races in various battleground states.

Former President Donald Trump won Montana handily in 2020, defeating President Joe Biden by 16.4 percentage points, and is expected to win by a wide margin in November. While Tester had managed to win reelection in the heavily Republican state in 2012 and 2018, polls indicate his luck appears to be running out in 2024.

The Real Clear Politics polling average shows Sheehy leading Tester, 50%-44.8%, and the Cook Political Report has rated the race as “lean Republican.”

In a recent AARP poll, Sheehy leads Tester, 51%-45%, in a head-to-head matchup, while in a matchup including libertarian and Green Party candidates, Sheehy’s lead over Tester grows to 49%-41%.