Michelle Malkin broke this story:

Obama for America
michelle –
Ask your Boss. Ask your Professor.
Take Election Day off and volunteer to make history.
Watch this video and sign up to help get out the vote on Tuesday, November 4th:
Watch the video
This election will be decided by what this grassroots movement can accomplish on Election Day.
We have volunteer shifts to fill throughout the day — make calls, knock on doors, and make sure your fellow voters get to the polls.
No previous experience is required. Sign up now to take the day off and make history on November 4th:
http://my.barackobama.com/takethedayoff
Thanks,
Jon
Jon Carson
National Field Director
Obama for America