A string of 2018 primary elections take place Tuesday, shaping elections that will help to determine which party holds the House and Senate after November's midterms.
Indiana, North Carolina, Ohio and West Virginia will hold primaries Tuesday. Both West Virginia and Indiana will hold critical Senate elections, while intriguing House and governor races will play out in Ohio and North Carolina.
West Virginia and Indiana have become top battlegrounds in the fight for the Senate, which Republicans currently control. Meanwhile, House races in both Ohio and North Carolina will factor into whether Democrats can win enough seats to take control of the chamber.
Here are some of the races to watch Tuesday: