Here is the announcement on his website:

Today, I am announcing, via Tweet, my candidacy for governor because California needs a new direction. Please join us as we build a campaign that does more than win an election – join us as we change California.

Here is the tweet that started the campaign:

It’s official- running for Gov of CA. Wanted you to be the first to know. Need your help. Check out video: http://tr.im/iOCN and ReTweet

And here is Gavin’s new video:

Gavin is a brilliant environmentalist and bold progressive leader. Enviroknow will be following the campaign closely.