The longest serving member of congress in history will be hanging up his boots after 29 terms in the House. Rep. John D. Dingell, D-Mich., has been one of the chamber’s most influential voices — he chaired the Energy and Commerce committee from 1981 to 1994, then again from 2006 from 2008. During his first stint as chairman, he greatly expanded the committee’s legislative reach. The Detroit Free Press reports that every four out of 10 bills in the chamber went through Energy and Commerce. His perch on the committee — to this day he sits on all six of its subcommittees — has made him a prime target of campaign cash from the energy industry he helped to regulate. Influence Explorer’s campaign finance data reveals the electric utilities industry has been the top contributor to Dingell’s campaigns since 1989, donating more than $1.4 million during this time.

Dingell’s friends in the automotive industry have also done their due diligence in supporting his campaigns. The two automotive juggernauts are Dingell’s two largest single benefactors. From 1989 to the third quarter of 2013, Ford’s PAC, employees and their family members had contributed $315,725, while General Motors gave $288,750. The longterm congressman has deep-rooted ties to American car manufacturers. Michigan’s 12th district includes Ford’s world headquarters (in Dearborn) and, until 2010, also boasted a General Motors plant in Ypsilanti. Dingell’s wife, Debbie, is the descendant of a General Motors’ founder, she chairs the Manufacturing Initiative of the American Automotive Policy Council, is a member of the Democratic National Committee and previously led GM’s government relations department.

As recently as June of last year, the octogenarian indicated that he was considering running again in 2014, telling the Detroit Free Press “we’re doing the things that you have to, to run.” His campaign committee showed no signs of slowing down, Sunlight’s Real-Time FEC shows John Dingell for Congress pulled in $108,624 in the fourth quarter, despite the fact that no one else has registered a campaign to run in the district. Like many longtime representatives, the majority of Dingell’s campaign funds have come from political action committees, rather than individual donors. Overall, 72 percent of his campaign war chest has come from PACs, compared to 28 percent from individuals.  A former member of the board of the National Rifle Association, the avid hunter would bring generous donors on duck and pheasant hunts in rural Maryland, invitations from Political Party Time reveal.

While federal law prohibits the congressman from converting his campaign funds to personal use, there are no such restrictions barring Dingell from using the money leftover in his leadership committee. As Sunlight reported on Feb. 20, there are 23 members leaving congress with surplus cash in their leadership PACs — how they will spend it is anyone’s guess. As of Jan. 31, Dingell’s Wolverine PAC had $31,275 in cash on hand, making the new grand total of leftover leadership dough $828,474.

The congressman’s wife, Debbie, has also made at least one appearance on the beltway fundraising circuit, co-hosting a fundraising reception for Sen. Amy Klobuchar, D-Minn., in 2011 at a Georgetown penthouse. Dingell’s wife is the presumptive favorite to replace her husband in congress, according to local Democratic consultants. Should she run, she will have a well-established national fundraising network to tap.