(CNN) President Donald Trump met with key senators at the White House on Thursday as the administration goes into a full-court press to nominate and confirm a new Supreme Court justice before the midterm elections next fall.

Trump met with three red-state Democrats who are all facing tough re-election fights this year: Sens. Joe Manchin, of West Virginia, Joe Donnelly, of Indiana, and Heidi Heitkamp, of North Dakota. The meetings came a day after Justice Anthony Kennedy announced he'll retire on July 31. The White House plans to nominate a new justice by July 9, CNN reported earlier Thursday.

Trump also met with Republican Sens. Lisa Murkowski, of Alaska, Susan Collins, of Maine, and Chuck Grassley, of Iowa. White House press secretary Sarah Sanders said Trump's team also talked with a dozen other senators.

"Tonight President Trump met with Senators Grassley, Collins, Murkowski, Manchin, Donnelly, and Heitkamp to discuss the Supreme Court vacancy," Sanders said in a statement. "The President's team also talked with more than a dozen other Senators today as part of ongoing outreach to get views and advice from both sides of the aisle on this important nomination."

All three Democratic senators are facing tough votes when Trump nominates a replacement for Kennedy. Their states went overwhelmingly for Trump in 2016 and a vote against the President's nominee to the court could end up costing them votes from Trump supporters they would have needed to stay in office.

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