In the Ohio governor's race, CNN projects that former Consumer Financial Protection Bureau head Richard Cordray will fend off former Rep. Dennis Kucinich for the Democratic nomination in the race to replace John Kasich, while Republican Attorney General Mike DeWine will best Kasich's lieutenant governor, Mary Taylor.
And in West Virginia, Democratic Sen. Manchin will fend off a primary challenge and is awaiting the winner of the Republican primary, CNN projects.
The political world is watching the Republican Senate primary in the state to see if ex-convict and coal baron Don Blankenship defeats Attorney General Patrick Morrisey and Rep. Evan Jenkins to take on Manchin.
Vice President Mike Pence's older brother, Greg Pence, won the Republican nomination for his congressional bid in Indiana, CNN projects.
There is also a GOP Senate primary in Ohio, another state where President Donald Trump won in 2016 and a Democratic incumbent is up for re-election this fall.
Rep. Jim Renacci takes on self-funding businessman Mike Gibbons in the GOP primary to face Democratic Sen. Sherrod Brown.
House races in Ohio and North Carolina will also get attention on election night.
In Ohio, the primaries for former GOP Rep. Pat Tiberi's 12th District seat will set up a potentially competitive August special election. In North Carolina, Republican Reps. Robert Pittenger and Walter Jones are attempting to fend off primary challenges.