Washington (CNN) President Donald Trump told Republican National Committee members in a closed-door gathering Thursday night that he'll travel to Nevada to back Sen. Dean Heller in a competitive Republican primary.

He also committed to trips to Minnesota -- where two Democratic senators are up for re-election this year -- as well as California and South Dakota, three sources in the room said.

Other states' delegations tried to get the President to promise visits there, as well. At one point, RNC Chairwoman Ronna McDaniel intervened and told the crowd to stop asking the same question. Trump began deflecting their requests to McDaniel.

Trump quizzed Nevada's delegation about how Heller's numbers looked headed into competitive match-ups in the GOP primary against Danny Tarkanian and, if he advances, in the general election against Democratic Rep. Jacky Rosen.

State GOP chairman Michael McDonald told Trump that Heller is in good shape. The two also talked briefly about the Las Vegas shooting.

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