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Here’s another link between Mayor Vince Gray‘s 2010 campaign and Jeff Thompson, the Medicaid contractor at the center of a federal investigation into campaign finance issues. The link: Gray’s campaign driver worked for a longtime associate of Thompson’s around the same time he was driving candidate Gray, according to campaign finance records.

Mark Long, who has run unsuccessfully for a couple of D.C. Council seats and currently works for Councilmember Vincent Orange, is listed on a campaign finance report from late 2010 as working for a company owned by Jeanne Harris, Thompson’s longtime associate. For much of that same year, Long was Gray’s campaign driver. (Here’s a video from primary day with Long driving Gray at a McDonald’s drive-thru.)

Disgraced former Ward 5 Councilmember Harry Thomas Jr.‘s Dec. 10, 2010, Office of Campaign Finance report indicates Long gave a $500 money order donation to the campaign in early November. The report lists Long as a consultant for Details International, the Harris-owned firm. Long’s $500 donation came on the same period as several other $500 money order donations from contributors with ties to Thompson.

Gray’s campaign records indicate that Long was not paid by the campaign for his long hours as a driver. Campaign records show Long was reimbursed $4,212.17 for “campaign materials” and “supplies.”

Why is this of interest? Well, LL and the Post have previously reported that the federal investigation into Gray’s campaign is looking into whether there was an an alleged off-the-books “shadow campaign.” The Post has detailed how one paid consultant of the alleged shadow effort says he was paid by Details International, just as Long evidently was. Federal authorities raided the homes of Harris and Thompson last month. The feds have also blanketed the Wilson Building with subpoenas seeking records related to the pair, as well as related to Details International.

Long has not returned several calls or an email seeking comment on the Thomas campaign finance report. In a brief conversation last week at Orange’s victory party, LL asked Long how he knew Harris. Long said Harris was a longtime family friend, but did not say whether he’d worked for her.