Karl Rove thinks President Trump should lower his expectations about a potential "red wave" in November's midterm elections.

Speaking on Saturday at a rally in Lewis Center, Ohio, Trump said those who are expecting Democrats to pick up multiple congressional seats will be "very surprised."

“They’re talking about this blue wave. I don’t think so,” Trump said. “I think it could be a red wave.”

Presidential Approval numbers are very good - strong economy, military and just about everything else. Better numbers than Obama at this point, by far. We are winning on just about every front and for that reason there will not be a Blue Wave, but there might be a Red Wave! — Donald J. Trump (@realDonaldTrump) August 5, 2018

On "America's Newsroom," Rove said it's rare for the party that holds the White House to gain congressional seats in a midterm election, noting that's only happened twice since 1934.

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He added, however, that the GOP may have a chance of gaining seats in the Senate because the landscape is extremely favorable, as ten of the 26 Democrats up for re-election are in states that Trump won in 2016.

"But in all likelihood, the Republicans are going to lose seats in the House, they're going to lose governorships, they're going to lose state legislative seats," Rove said.

"I think the president would be well-advised to say we face an uphill fight but he feels good about it, rather than set the expectation that somehow or another the Republicans are going to gain across the board with a red wave."

He said Tuesday's special election in Ohio's 12th Congressional District between Republican state Sen. Troy Balderson and upstart Democratic challenger Danny O'Connor is extremely important because it's a close race in a historically Republican district.

"The Democrats are pushing a big run on it. They'll get a big psychological boost if they win it," Rove said.

Watch more from "America's Newsroom" above.

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