The Obama campaign today launched a Tumblr for the 2012 campaign in an effort to engage younger voters seen as a key constituency for the president’s re-election bid.

Aides made the announcement on Twitter, via @BarackObama, underscoring the importance of social media users – and Obama’s 10.7 million followers – to the campaign.

A blog message on the Obama Tumblr page asks supporters to submit anecdotes, photos, videos and links related to their involvement with the campaign to create a “collaborative storytelling effort.”

“Upload a photo of 2012 t-shirts or signs you see out in the wild,” the message reads. “Pass along jokes, particularly if they’re funny.”

As for contributions from Obama critics, the campaign acknowledges that it expects them to be part of the mix.

“There will be trolls among you: this we know,” according to the message. ”We ask only that you remember that we’re people—fairly nice ones—and that your mother would want you to be polite.”