WASHINGTON (AP) -- Leaked audio in Nevada reveals a Republican Senate candidate trashing her party. Video of a Democratic Senate hopeful wrongly claiming he served in Vietnam becomes a TV ad in Connecticut. A housekeeper steps forward to say her employer, California's GOP gubernatorial nominee, knew she was an illegal immigrant.
Digging for dirt, political foes are working overtime to surprise rivals with skeletons and other embarrassments, forcing them to defend themselves rather than focus on their closing arguments in the homestretch of critical midterm elections.
Control of Congress and of statehouses nationwide is at stake on Nov. 2, and -- behind the scenes or sometimes in plain sight -- both Republicans seeking power and Democrats looking to retain it are laboring to unearth and highlight stains in opposing candidates' backgrounds. Both sides are using the material to question candidates' character and trustworthiness, important issues with voters who are already sour on politicians in general.
In one of the latest episodes, GOP Senate nominee Sharron Angle in Nevada was recorded criticizing Washington Republicans in a conversation with tea party hopeful Scott Ashjian, whose third-party candidacy threatens to siphon votes from her and help Senate Democratic leader Harry Reid win re-election.
"The Republicans have lost their standards, they've lost their principles ... really that's why the machine in the Republican Party is fighting against me. They have never really gone along with lower taxes and less government," Angle said, according to a recording that reached the Las Vegas Sun. The newspaper didn't say where it got the recording but Ashjian told MSNBC he taped the meeting by concealing a recorder in his pocket.
Reid's campaign used the GOP nominee's comments to claim "Angle will say or do anything to get elected."
That incident followed a political bombshell that shook the California governor's race last week.
GOP nominee Meg Whitman was forced to answer for employing an illegal immigrant for nine years when the Mexican maid -- and her attorney, longtime Democratic supporter Gloria Allred of Los Angeles -- stepped forward to claim that Whitman had known about her status since 2003. Whitman disputed that and dismissed the allegations as a baseless stunt engineered by Democratic opponent Jerry Brown.
"Jerry, you should be ashamed," Whitman told Brown in a weekend debate. "You and your surrogates ... put her deportation at risk. You put it out there and you should be ashamed for sacrificing Nicky Diaz on the altar of your political ambitions."
Brown, in turn, accused Whitman of refusing to take responsibility: "You have blamed her, blamed me, blamed the left, blamed the unions. But you don't take accountability."
In Connecticut, Republican Linda McMahon rolled out a TV ad on Monday that showed a 2008 clip of Democratic Senate nominee Richard Blumenthal's now-discredited comment about "the days that I served in Vietnam." The controversy surfaced in the spring, putting a chink in the Democrat's campaign in what some strategists called the opening salvo in the opposition-research wars. The ad takes it to the next level, asking: "If he lied about Vietnam, what else is he lying about?"
McMahon, the former World Wrestling Entertainment executive, also is finding herself the target of an unflattering disclosure: media reports of a contract involving her wrestling empire teaming with the company that produces the "Girls Gone Wild" videos and promoting a 2003 "uncensored" pay-per-view spring break special.
There's almost surely more to come.
"Some of these stories, if they check out and if they get legs they can really affect how people vote. In close races, opposition research can make a difference," said Mike Gehrke, who spent several election cycles as a Democratic opposition researcher.
But opposition research can backfire or simply fall flat.
"There are so many different channels for it now -- TV ads, web videos, e-mail, blogs, radio, direct mail. The message can become so fractured that people tune it out," said Kevin Madden, a Republican communications strategist. "It has to be potent."
Political operatives on both sides compile reams of information on candidates' personal backgrounds and professional records. Divorce files and housing documents are mined. Video appearances and audio recordings are collected. Rumors of wrongdoing are chased down.
Politically damaging disclosures eventually are leaked by allies to local media outlets or posted without fingerprints on the Internet, giving candidates plausible deniability so voters don't hold them accountable for negative campaigning. In many cases, the information finds its way into TV ads in a campaign's final weeks.
Timing is important: Plant information too early and voters may forget about it, too late and they may not learn about it before heading to the polls.
And so, with four weeks until Election Day, the disclosures and allegations pile higher.
House Democrats are contending that eight Republican hopefuls around the country "with disturbing backgrounds and legal problems" were recruited and endorsed by House GOP leaders. A news release asks: "Did Republican leaders know -- or just not care -- about their Republican recruits' lies, harassment of women, lawsuits, tax cheating, assault and altogether negligent behavior?"
One of those candidates, Tom Ganley in Ohio, is having to respond to a lawsuit filed by a 39-year-old Cleveland woman who says he propositioned and groped her in 2009 after she tried to volunteer for his campaign. Ganley denies the accusations, and his lawyer contends there's a political motive.
In New Jersey's 3rd Congressional District, a new TV ad by Democratic Rep. John Adler accuses GOP challenger John Runyan of trying to call his massive house a farm. Says the ad: "Runyan bought one donkey to get a $20,000 tax break by saying he lives on a farm. Luckily he was caught."