Few Democrats are expected to support his nomination and some have promised to filibuster when the vote reaches the floor.
Both Senators have met with Gorsuch and cited his judicial record and praise from colleagues as some of the reasons for their support.
Manchin called him an "honest and thoughtful man" in a statement, saying "I hold no illusions that I will agree with every decision Judge Gorsuch may issue in the future, but I have not found any reasons why this jurist should not be a Supreme Court Justice."
Heitkamp cited Gorsuch's experience with tribal law and public lands issues, as well as endorsements from Native American organizations.
"He has a record as a balanced, meticulous, and well respected jurist who understands the rule of law," she said in the statement.
"I was taught that two wrongs don’t make a right. There isn’t a perfect judge," Heitkamp said in the statement. "Regardless of which party is in the White House, the U.S. Supreme Court should be above politics."