With Colorado a state that could shift the balance of power in the U.S. Senate, many an eye is on the matchup between the incumbent Democat, Sen. Mark Udall, and his Republican challenger, Rep. Cory Gardner.

Colorado also is one of three states conducting “all mail” voting this year, meaning registered voters get a ballot in the mail but still have the option of voting in person. The process, though, is a popular avenue for voter fraud.

In this new video from Project Veritas, a nonprofit dedicated to exposing government corruption and other misconduct, undercover filmmaker James O’Keefe catches Udall supporters on camera appearing to condone voter fraud through the all-mail system.

Polls show Gardner continues to to hold a lead over Udall. According to the latest poll from USA Today, Udall trails by seven points.

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