NEW PHILADELPHIA, Ohio — Bemoaning a “culture of corruption” in the Republican Party, Democrats are convinced that they have a winning election-year issue.The GOP claims it is a wash.

Allegations of criminal wrongdoing and ethical lapses among lawmakers shadow several House and Senate races from Ohio to Texas and Louisiana to Montana this midterm election.

“We need a new direction that restores honesty to the People’s House,” Democratic leader Nancy Pelosi of California said recently, emphasizing one of her party’s campaign messages as scandal-scarred Republican Rep. Bob Ney of Ohio abandoned his re-election race.

Out of power for a dozen years, Democrats are trying to persuade voters to give them the reins of Congress by arguing that ethics questions surrounding a few Republicans are part of a broad pattern of corruption in the GOP.

The Democrats’ effort, however, has been muddied by similar woes in their own ranks, which Republicans gleefully point out as they try to inoculate themselves from Democratic attacks.

GOP leaders also have sought to undercut the Democrats’ strategy by pressuring two congressmen facing corruption allegations — Mr. Ney and former House Majority Leader Tom DeLay of Texas — to end their re-election bids.Party leaders wanted to make way for unscathed candidates. Despite such maneuvers, GOP leaders brush aside any notion that corruption will become a national issue that will motivate voters to dump Republicans on November 7.

“All politics is local,” Rep. Tom Reynolds, a Republican of New York and the chairman of the House Republicans’ campaign committee, said recently.

However, polls show the corruption issue may have legs. Nearly half of those surveyed in a Gallup poll in June identified “corruption in government” as “extremely important” to their vote for Congress this year. That poll also found that the public trusted Democrats over Republicans — 44% to 24% — to do a better job dealing with the issue.

This month, Mr. Ney became the latest Republican to see his political career end amid a corruption investigation. He has not been charged and insists that he is innocent. Yet the six-term congressman’s links to Jack Abramoff, who is at the center of a Washington lobbying scandal, hang like a cloud over the district.

Everyone seemed to have an opinion about the race on the day the local newspaper headline screamed “Ney drops out.” Some said it was about time that he abandoned his bid while others wished he would have stuck it out. Detractors characterized him as shady, but fans described him as a beloved congressman who served the region well.

One thing voters in the district that snakes from central Ohio south seemed to agree on — they will vote for the candidate that they trust the most.

“Zack Space is an honest man,” Rick Critchhow, a Democrat who voted for President Bush in 2004, said of the party’s nominee as he sipped coffee at the Daily Grind Cafe with his buddies. All were down on Mr. Ney.

Another regular, Jim Swinderman, said the congressman’s favored Republican replacement on the ballot, state Senator Joy Padgett, has a lot to prove. “We don’t know her. She’s just a face,”he said, pointing to a newspaper snapshot.

Across town, at a groundbreaking ceremony for a technology business park, Tom Hackenbracht and Paul Hickman, both Republicans, praised Mr. Ney’s “outstanding record” and lamented what they called a big loss for the district.

“It’s very easy to criticize someone in a leadership capacity, and, so many times, you forget the good that’s been done,” Mr. Hickman said. Forced to choose someone instead of Mr. Ney, Mr. Hackenbracht said: “I’m excited about Joy Padgett. She’s an excellent candidate.”

Republicans are banking on voters like them to help the GOP retain the district. It had been considered one Democrats could win in the fall, but the GOP’s chances brightened with Mr. Ney off the ballot.