The nomination battles for open Senate seats in Pennsylvania and North Carolina that will be settled Tuesday have already consumed $127 million, a figure that will likely be matched or even topped before November as both states become battlegrounds for control of the 50-50 chamber.
On top of that, a slew of retirements, new districts created through reapportionment and a couple of House members deciding to make Senate runs also means there are nine House districts without incumbents in states holding primaries on Tuesday.
Here’s a look at those races.
