Stephen Colbert Got 600 People to Participate in His Latest Promo

August 16, 2015 2:20 PM EDT

Stephen Colbert has been doing everything from hanging out with Mitt Romney to appearing on public access television to promote next month’s launch of The Late Show with Stephen Colbert.

On Sunday, he rallied about 600 fans in New York’s Union Square for what is thought to be his latest promo. Based on social media accounts, the event featured Colbert speaking to the crowd over a megaphone from the back of a truck and the fans holding balloons in the air and cheering.

Colbert’s Late Show will premiere on Sept. 8. Jeb Bush and George Clooney will be his first guests.

Hanging out with 600 friends in Union Square this morning! Thanks for braving the heat! #LSSC pic.twitter.com/Pw4dMgogX0
— Stephen Colbert (@StephenAtHome) August 16, 2015

This pretty much sums it up @colbertlateshow #supersecret taping #LSSC @StephenAtHome pic.twitter.com/ibwTFxderq
— Amanduh Marcuson (@PHAT_GOOBY) August 16, 2015

Right now: Stephen Colbert (I think) addressing crowd at Union Square pic.twitter.com/HxwHM5KX5K
— Jon Levine (@LevineJonathan) August 16, 2015

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