Kamala Harris was considering Mark Cuban as her running mate, but the billionaire flat out rejected the campaign, explaining he wasn't the type to play second fiddle ... saying for that reason, I'm out!
Cuban recently joined "The Bulwark" podcast ... when host Tim Miller asked him about "some green room gossip" he'd heard suggesting Mark was on the short list for the veep gig.
The former "Shark Tank" star confirmed the rumor, and revealed why and how he told the Harris campaign he wasn't interested.