Democrats have newfound optimism following midterm victories in states that President Trump Donald John TrumpBiden on Trump's refusal to commit to peaceful transfer of power: 'What country are we in?' Romney: 'Unthinkable and unacceptable' to not commit to peaceful transition of power Two Louisville police officers shot amid Breonna Taylor grand jury protests MORE won in 2016, Brookings Institution fellow Elaine Kamarck said on Friday.

"I think Democrats really feel they're catching up, and I really feel that Democrats have a sort of new lease on life," Kamarck, who is also the director of the Center for Effective Public Management at Brookings, told Hill.TV's Jamal Simmons on "What America's Thinking."

She pointed to the governor's races in Michigan, Pennsylvania and Wisconsin, noting that those are three states that former Secretary of State Hillary Hillary Clinton Hillary Diane Rodham ClintonDemocratic groups using Bloomberg money to launch M in Spanish language ads in Florida The Hill's Campaign Report: Presidential polls tighten weeks out from Election Day More than 50 Latino faith leaders endorse Biden MORE had been expected to win in 2016. Trump's unexpected victory in 2016 was due in large part to his ability to break through the so-called blue wall in those states.

"They all are now in control of Democratic governors," Kamarck said. "I think that's making Democrats feel really optimistic in the future."

During last week's midterm elections, Wisconsin Gov. Scott Walker (R) was unseated by Democratic challenger Tony Evers, while Gretchen Whitmer (D) defeated the Michigan Attorney General Bill Schuette (R) in that state's gubernatorial race.

Pennsylvania Gov. Tom Wolf (D) successfully defended his seat, deflecting a challenge from Republican Scott Wagner.

— Julia Manchester