Primary elections

After a brief lull, primary elections are kicking back into gear Tuesday in four states. It's the start of a busy stretch of important races between now and Labor Day.

Voters in Kansas, Michigan, Missouri and Washington head to the polls. There's a lot going on.

Below we break down the four most important things you should watch. As always, stay tuned for results this evening right here on Post Politics.

1. Will Sen. Pat Roberts get past his tea party challenger?



Roberts has made a couple of big mistakes, but he is favored to win. It all started with a February New York Times story revealing the senator pays rent to supporters to stay with them when he's in Kansas, instead of residing at his own house. The story fueled the kind of "he's lost touch with the state" criticism that dislodged Richard Lugar from the Senate in 2012. (Roberts owns a home suburban Washington.) Even worse, Roberts seemed oblivious to how bad it looked, jokingly telling the Times, "I have full access to the recliner." It didn't help when he remarked in July radio interview, "Every time I get an opponent — I mean, every time I get a chance, I’m home."

But here's the thing: Milton Wolf has not been able to capitalize. Wolf -- a second cousin of President Obama -- has his own problems. The doctor posted graphic X-ray images of gunshot victims on Facebook and made crude jokes about them. He has been outspent nearly 3 to 1. And while he's gotten some help from national tea party groups like the Senate Conservatives Fund, he is hardly the national tea party darling that Chris McDaniel was in Mississippi against Sen. Thad Cochran.

National Republican Senatorial Committee Chairman Jerry Moran (Kan.) didn't sound too worried about Roberts last week in a briefing with reporters. Polls have tightened a bit, but they still mostly show Roberts leading comfortably. This is one of the final chances for the tea party to knock off a sitting senator in a primary this year.