"What is this Snapshot thing and why do I only get ten seconds?" tweeted the Vermont independent senator.

Snapchat (not "Snapshot") is a mobile app for sharing videos and pictures that quickly disappear, and Sanders — or at least his digital savvy team — likely knows exactly what it is.  The new platform adds to a strong digital presence for the Democratic presidential hopeful.

Sanders, wearing a button-down shirt and a sweater, posted his first broadcast on his way to Cleveland Monday, counting down "three, two, one" at the beginning.

"Join the political revolution," he says. "Help us make real change in America."

Snapchat users can see Sanders' snaps, but they can't snap back because the campaign says it isn't adding friends yet.

Sanders has used Twitter for live-tweeting to his 871,000 followers during Republican debates. He has also long interacted with subscribers of Reddit, an online message board, doing periodic posts and fielding questions during three "Ask Me Anything" sessions since 2013.

The "Sanders For President" subreddit, launched by his supporters, has helped boost momentum for his campaign.