But the contest over the first-in-the-nation primaries has also become a proxy war over the future of the Party. The D.N.C.’s decision, expected by late summer, could have a significant effect on the 2src28...

The Memorial Day parade in Eastpointe, a Detroit suburb, is a dependably wholesome, all-American affair, with Odd Fellows, Elks, library friends, and firefighters marching past flag-bedecked telephone poles and bunting-laden ranch houses. Eastpointe is...