• Ohio, West Virginia, Indiana and North Carolina are holding primary elections on Tuesday.

• Republicans chose Senate nominees who will challenge Sens. Joe Manchin, Joe Donnelly and Sherrod Brown.

• Voters are also choosing nominees for some House districts expected to be competitive in November.

The first major round of primary elections take place Tuesday, with stakes for control of the House and Senate after November's midterm elections.

In West Virginia , Indiana and Ohio , Republicans chose nominees who will challenge Democratic Senate incumbents later this year. In some safe House districts, the primary winner will effectively determine the general election victor. In other competitive districts, the major parties will determine who will fight for a House seat later this year.

The most closely watched race Tuesday takes place in West Virginia, where Republican leaders got their wish as ex-convict Don Blankenship fell well short of winning the Senate primary. The GOP worried the brash-ex coal baron would have struggled to defeat Democratic Sen. Joe Manchin in a general election.

With polls closed in all states holding primaries Tuesday, here are some of the notable results, according to NBC News (results will be updated throughout Tuesday night):

• Attorney General Patrick Morrisey is projected to win the West Virginia GOP Senate primary , according to NBC News. Blankenship conceded the race as he lagged behind both Morrisey and Rep. Evan Jenkins for the nomination. On the Democratic side, Manchin is projected to beat challenger Paula Swearengin, according to NBC. Trump won the state by about 40 percentage points in 2016.

• Businessman and former state Rep. Mike Braun is projected to win Indiana's GOP Senate primary , according to NBC. He is projected to defeat Reps. Todd Rokita and Luke Messer in the race. Braun will challenge Democratic Sen. Joe Donnelly , who ran unopposed. President Donald Trump won the state by about 20 percentage points in 2016.

• Trump-backed Rep. Jim Renacci is projected to win the GOP Senate primary in Ohio, according to NBC. He will face Democratic Sen. Sherrod Brown , who ran unopposed.

• Former Consumer Financial Protection Bureau Director Richard Cordray is projected to win Ohio's Democratic gubernatorial primary, according to NBC. He is projected to defeat former congressman and presidential candidate Dennis Kucinich, who tried to cast himself as a more progressive candidate and win over the state's Democratic base. Cordray was considered more competitive statewide. Ohio Attorney General Mike DeWine is projected to win Ohio's Republican gubernatorial primary, according to NBC. He is projected to beat Lt. Gov. Mary Taylor. Cordray and DeWine will compete to replace GOP Gov. John Kasich, who is term limited.

• Democratic candidate Danny O'Connor, the recorder in Ohio's Franklin County, is projected to win the primary for the Ohio 12th District special election in August, according to NBC. While the seat is not normally in play for Democrats, the party hopes it can add to a recent string of success in special elections. NBC had not called the Republican primary shortly before 11 p.m. ET on Tuesday.

• Greg Pence, Vice President Mike Pence brother, is the projected winner of Indiana's 6th District GOP primary. He will be a heavy favorite to win the district, currently held by Messer, in November. Mike Pence previously represented the district in Congress.