I've never heard Perriello speak; does he have Obama or even Kander-level youthful charisma? Because you need to be kind of that type of legendary charismatic figure that Obama was when he gave his speech as a state senator to have that sort of quick meteoric rise IMO.
He'd be governor for 1 year and then basically have to start frantically laying the seeds for a 2020 run, seems implausible if he isn't already currently in 2017 being whispered about as a presidential figure by the Dem establishment like Obama was circa 2004.
ETA: Schumer and other party leaders helping and even pushing obama into laying a 2008 groundwork was vitally important to both his decision to run and his win
I saw his recent interview on MSNBC and he looked very strong. He's really good at talking about issues that the working class want to hear. If he manages to win the primary after an endorsement from say, Sanders, I think he'd be an interesting candidate for 2020.