"Obama's building a political machine," said Stephen Hess, a presidential scholar at the Brookings Institution, a center-left Washington research group.

"These people have just opened up a new world for politics," added Hess, the author of "What Do We Do Now?: A Workbook for the President-Elect."

Pre-Internet presidents, he said, lacked the ability to communicate in real time with masses of their volunteers. In addition, the social networks such as MySpace and Facebook that link Obama's army together didn't exist.

The net effect was that pre-Obama political machines grew out of local politics and remained rooted there. Statewide or presidential candidates relied largely on local leaders' support.

Not so Obama, who, at least for now, has the allegiance of thousands of volunteers in most if not all congressional districts.

"Your hard work built this movement," Plouffe wrote them. "Now it's up to you to decide how we move forward."

His four-page questionnaire also asks respondents to name their top-priority issues out of 27 listed. The options included environment and global warming, civil rights and voting rights, war in Iraq, jobs and trade, or divisive politics and partisanship.

Plouffe also invited volunteers to identify their proudest campaign accomplishment and, separately, to name a fellow volunteer or field organizer who inspired them.