The Montana Supreme Court on Tuesday affirmed a lower court ruling which allowed the state’s Green Party Senate candidate to remain on the ballot in November, a blow to Democrats’ efforts to prevent what they expect could be a spoiler in the close race between incumbent Sen. Jon Tester (D-Mont.) and his challenger, Tim Sheehy (R). The Montana Democratic Party (MDP) filed a lawsuit in late August contesting the nomination of Green Party candidate Robert Barb, who placed second in the state’s Green Party primary but replaced the primary’s top vote-getter after the winner dropped out of the race. The Green Party submitted the necessary paperwork to the secretary of state declaring Barb the replacement candidate for the Green Party, but the MDP argued in its lawsuit that the Green Party did not follow proper protocol and sued to block Barb’s name from appearing on the ballot. In its ruling on Tuesday, the state’s Supreme Court determined the MDP “failed to demonstrate that it is likely that the Montana Green Party violated its party ‘rules’ when its state central committee appointed Barb to fill the vacancy.” The court agreed with the defendant’s argument pointing out that the Green Party bylaws “are silent” on how the party should replace a candidate who drops out, so “MDP’s allegation that the Montana Green Party failed to appoint Barb in accordance with its bylaws is merely speculative.” The ruling affirms a lower court ruling denying MDP’s request for injunctive relief, arguing the MDP did not follow the “express and exclusive statutory process for contesting nominations” and was therefore unlikely to succeed in making its case. The Montana Supreme Court disagreed with the lower court’s reasoning but ultimately arrived at the same conclusion. MDP Chair Robyn Driscoll said the ruling was “disappointing,” in an emailed statement Wednesday, taking aim at both Barb and the Montana Republican Party. “While today’s ruling is disappointing, the Montana Democratic Party will continue to make sure that voters know the truth about Robert Barb: He is a well-known Republican who shares right-wing conspiracy theories and believes climate change is a ‘B.S. fake narrative,’” Driscoll said in the statement. “We strongly condemn the Montana Republican Party’s blatant manipulation of voters and troubling refusal to follow Montana election law, and we will continue to share the truth from now until Election Day,” Driscoll added. The Hill has contacted the Green Party for a response. The court decision comes as the Democratic incumbent in the Senate fights to retain his seat in the deep-red state of Montana, which will prove critical in determining control of the upper chamber. The Cook Political Report recently made a “major shift,” moving the Montana Senate race from “Toss Up,” to “Lean Republican,” as Republicans increasingly like their odds of defeating the incumbent in the battleground state. Several recent polls have shown GOP businessman Sheehy leading Tester by a few points, within the margin of error but short of what Democrats would like. An AARP poll from last month showed Sheehy leading Tester by 6 points, while an internal poll from the Senate Republicans’ campaign arm had Sheehy leading by 4 points.