Sept. 18 (UPI) — A Green Party candidate for the U.S. Senate must be included on the Montana ballot for the Nov. 5 election, the state’s Supreme Court ruled Tuesday.

The ruling denies the Montana Democratic Party’s efforts to exclude Green Party candidate Robert Barb from the ballot, which could tilt the election in favor of Republican challenger Tim Sheehy over Democrat incumbent Sen. Jon Tester.

A Tester loss also might tilt control of the U.S. Senate in favor of the Republican party.

The Montana Democratic Party in August sued Montana Secretary of State Christi Jacobsen and the Montana Green Party to remove Barb from the ballot.

The state Democrats argued the Green Party made a late change of its candidates and said the sudden change should exclude Barb from ballot eligibility.

Lewis & Clark County District Court Judge Mick McMahon in late August ruled against the state’s Democratic Party, which prompted an appeal to the Montana Supreme Court.

The state Supreme Court in its ruling Tuesday said Democrats did not “demonstrate that it is likely that the Montana Green Party violated its party ‘rules’ when its state central committee appointed Barb to fill the [candidate] vacancy.”

The Green Party successfully argued that it has “silent” bylaws regarding replacing candidates who end their candidacy and there is no specific process within the Green Party for replacing former candidates.

The lower court and the state Supreme Court each ruled the Montana Democratic Party’s argument was “merely speculative” regarding whether or not the Green Party followed an “express and exclusive statutory process for contesting nomination.”

The speculative nature of the state Democrats in opposing inclusion of the Barb as the Green Party’s Senate candidate means they are unlikely to prevail in the matter, Judge McMahon and the Supreme Court ruled separately.

The state Supreme Court also denied the Democratic Party’s request to intervene and approve an injunction against Barb’s candidacy.

Montana Democratic Party chair Robyn Driscoll responded to the ruling in an emailed statement accusing Barb of being a “well-known Republican who shares right-wing conspiracy theories and believes climate change is a ‘B.S. fake narrative,” the Hill reported.

Barb’s inclusion on the ballot as a Green Party candidate could siphon off votes for Tester, who has been losing ground against Sheehy and no longer is favored to win another term in the Senate.

Former President Donald Trump’s bid for a second term in the White House also might help Sheehy defeat Tester, which many political analysts say could make the GOP the majority party in the U.S. Senate.

Trump won Montana over President Joe Biden by 16 points during the 2020 election.