The Politico's Jonathan Martin broke the story:

Soren Dayton, who works in McCain's political department, sent out the YouTube link of "Is Obama Wright?" on Twitter at 12:31 Thursday with the tag, "Good video on Obama and Wright."  It has since been taken down.

Since Martin’s post, Dayton’s entire twitter account has been deleted.  Dayton’s LinkedIn profile still states that he is a current employee in John McCain’s Political Department; his employment time dates from January 2007 – Present.  Dayton describes the job as, “I do a bunch of things in the political shop.”

ZDNet defines a twitter as, “A Web site and service that lets users send short text messages from their cellphones to a group of friends. Launched in 2006, Twitter was designed for people to broadcast their current activities and thoughts."

Dayton has supporters who feel that the McCain camp overreacted to the Twitterpost.  The facebook group created by Joshua Trevino, “Support Soren Dayton!” calls for McCain “to FIGHT, not roll over at the merest hint of controversy.”  In an effort to salvage Dayton’s position, the  group's 181 members have been encouraged to voice their opinion to various McCain contacts, including Michael Palmer, the head of the e-campaign for John McCain, and McCain's blog outreach guy, Patrick Hynes.

McCains campaign has reacted with the following statement:

"We have been very clear on the type of campaign we intend to run and this  staffer acted in violation of our policy," McCain spokeswoman Jill Hazelbaker said. "He has been reprimanded by campaign leadership and suspended from the campaign."

Washington Post's Coverage