The contours of a premier Senate race took shape in Iowa, while President Donald Trump’s endorsement streak ran into a roadblock there.

Six states will hold primaries on Tuesday: California, Iowa, Montana, New Jersey, New Mexico and South Dakota. Will a Democrat advance in California’s governor’s race? Can Spencer…

The winners will compete in November’s critical midterm elections, in which Iowa’s U.S. Senate and House seats could determine control of the narrowly divided chambers.