Rep. Doug Lamborn, R-Colo., may not be on the ballot this fall thanks to a petition snafu.

The Colorado Supreme Court ruled Monday that the signatures the six-term congressman submitted to run for re-election were invalid because the people he hired to gather those signatures were not Colorado residents, as required by state law. Therefore, the court ruled those signatures were "invalid and may not be considered," leaving him short of 1,000 needed to make the ballot.

A lower court had initially ruled in Lamborn's favor, but five Republicans in his district appealed and the state Supreme Court sided with the congressman's opponents.

"We recognize the gravity of this conclusion, but Colorado law does not permit us to conclude otherwise," the court wrote in the ruling.

According to member station KUNC, it's too late for Lamborn to wage a write-in campaign to get on the June 26 primary ballot, but the secretary of state's office says he could be write-in candidate for the general election.

Lamborn could still, however, appeal the state court's decision to a federal court. The Denver Post reports that could be by asking the court to change the requirement for petition gatherers to the standard applied to those gathering signatures for ballot initiatives, who aren't required to live in the state.

When the Post reached Lamborn by phone, he told the paper "we're still digesting the opinion" and then hung up. When he was reached a second time, he said "we're still looking at the language" and hung up again, directing the reporter to his press secretary, the paper reports.

Lamborn represents a safe Republican seat that includes Colorado Springs. President Trump carried by 24 points, and even if Lamborn isn't on the ballot it's unlikely the seat would fall into Democratic hands.

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