Though retiring Rep. Tom Davis (R-Va.) expects losses for House Republicans numbering in the double digits this year, he said Friday that races will tighten as Election Day approaches.

"I've seen some races that have swung 25 points in 10 days," said Davis, former chairman of the National Republican Congressional Committee, at the National Press Club.

Davis, appearing with Democratic Congressional Campaign Committee Chairman Chris Van HollenChristopher (Chris) Van HollenWhere Dems stand on Sanders's single-payer bill Overnight Regulation: DeVos ignites backlash with rewrite of campus sexual assault policy l EPA power plant rule decision likely this fall | Panel approves Trump financial regulator nominees Overnight Finance: Senate approves Trump's debt deal with Dems | Conservatives fume at GOP leaders -- not Trump | Trump wants to talk about killing debt limit | Panel approves Fed, comptroller nominees MORE (Md.), also cited difficulties that Democrats face this year.

"They've got some poster people themselves," Davis said.

He said that Democrats, who ran against lobbyist Jack Abramoff's "culture of corruption" in 2006, face their own ethics issues this year. He noted that Democrats up for re-election include Rep. William Jefferson (La.), who awaits trial on federal corruption charges, and House Ways and Means Chairman Charles Rangel (N.Y.), who faces House ethics probes for his real-estate deals.

Unlike Davis, Van Hollen stayed away from predicting the number of seats Democrats could win.

"The environment is very turbulent out there," he said, noting a large number of toss-up races.

When asked about specific toss-up races that their respective sides are eyeing, Davis singled out Democratic Reps. Paul Kanjorski (Pa.) and Carol Shea-Porter (N.H.). Van Hollen said that GOP Reps. Randy Kuhl (N.Y.), Marilyn Musgrave (Colo.) and Ric Keller (Fla.) could all lose.