Examiner.com article on U.S. House primaries

John Dingell is once again the Democratic nominee for Michigan's 12th Congressional District.
Three of four contests decided for U.S. House in Washtenaw County

With 83% of the precincts reported in Washtenaw County as of 1:30 A.M., the Associated Press has called the winners of both the Republican and Democratic primaries in the Seventh Congressional District and the victor of the Democratic primary in the Twelfth Congressional District.

Incumbent Tim Walberg successfully fended off a primary challenge from Dan Davis to be the Republican nominee to be the Republican nominee for the Seventh Congressional District. Walberg will face Kurt Haskell, who defeated Ruben Marquez to become the Democratic nominee.

Democrat John Dingell, the longest serving current Representative in the House, survived a challenge from Daniel Marcin for his party's nomination for the Twelfth District seat. Dingell's opponent has not yet been determined, as the Associated Press has not yet called the winner of the Republican primary between Cynthia Kallgren and Karen Jacobsen, which Kallgren leads narrowly.

Details for all four primaries at the link in the headline.

As for what this means, both incumbents will very likely win. Haskell has a reputation as a flake (or worse) and Kallgren is too far right for the district. In the case of Dingell, that's sweet. In the case of Walberg, it's quite bitter. I used to live in his district and can't stand the man.