Washington (CNN) The Colorado Supreme Court kicked Republican Rep. Doug Lamborn off the primary ballot Monday, throwing the six-term lawmaker's political future into doubt.

The court ruled that a person who Lamborn had hired to circulate petitions to get on the ballot lived out of state, which invalidated the signatures that person had gathered and pushed Lamborn below the state's 1,000-signature threshold to qualify for the ballot.

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

Asked about Lamborn's next legal steps, his House office referred a reporter to his campaign. Campaign officials didn't immediately respond to a message seeking comment.

The Colorado Springs-based 5th district, represented by Lamborn since 2007, is heavily Republican. President Donald Trump won there by 24 percentage points in 2016 and Mitt Romney carried it by 21 points in 2012.

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