(CNN) A former FBI employee is running for Congress as the "Cannabis Candidate," with a campaign ad featuring him smoking marijuana in front of an image of the American flag.

Benjamin Thomas Wolf is one of three challengers to incumbent Rep. Mike Quigley in the Democratic primary for Illinois' 5th Congressional District, which includes parts of Chicago.

The campaign ad, shot in Wolf's apartment, was a way to let voters who are in favor of marijuana legalization know that "there are people that hear them and agree with them and will stand up for what they think is important," Wolf said.

"It was my idea. I knew that we needed to do something with cannabis -- to take a little bit of a risk, but at the same time connect with the voters," he told CNN in a phone interview Wednesday.

Wolf said he believes that legalizing marijuana in Illinois would reform the criminal justice system and bring in billions in tax revenue.

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