One of Grimm's top fundraisers is currently imprisoned for visa fraud
and faces increased extortion and money laundering charges. Rivera faces a federal investigation into allegations he engaged in a shadow campaign to back an opponent to the ultimate winner of the Democratic primary in his district, Joe GarciaJoe GarciaWake up, Democrats — Koch empire targets 2016 Hispanic vote Immigration action jolts '16 races WHIP COUNT: Mad scramble for votes to keep government funded MORE. And Buchanan has been under various investigations, including ones launched by the House Ethics Committee and the Department of Justice, into possibly illegal campaign donations. He was cleared by the DOJ of any wrongdoing on Tuesday.
Ferguson's reference to the GOP's "zero tolerance" policy comes from a conversation House Majority Leader Eric CantorEric CantorRepublicans who vow to never back Trump NRCC upgrades 11 'Young Guns' candidates Cruz, Kasich join forces to stop Trump MORE (R-Va.) had with National Review Online in 2010 in which he said that charges of ethics violations against Reps. Charles Rangel (D-N.Y.) and Maxine Waters (D-Calif.) were evidence then-Speaker Nancy Pelosi (D-Calif.) had failed to clean up the culture in Washington.
"As Republicans emerge as a new governing majority, it is incumbent upon us to institute a zero tolerance policy" when it comes to ethics violations, Cantor says.
He adds that ethics violations were part of the reason Republicans lost so many members in 2006 and 2008, and insists that "we've learned our lesson."
"We cannot tolerate any ethics violations or behavior in terms of compromising the ethics that the people expect us to have as their representatives," he says.
Cantor's assertion, that ethics violations might have been part of the reason Republicans lost seats in 2006 and 2008, could resonate with these three incumbents as well. Each is facing a tight race for reelection, despite the fact that each is also running in a Republican-leaning district, and the persistent competitiveness of their races could be due in part to the investigations and allegations of misconduct swirling around each.
That's not to say, though, that Democrats don't have their fair share of scandal-plagued candidates — the Republican counterpart to the DCCC launched a similar campaign last week to spotlight the "10 Most Corrupt Democrats" nationwide.
Last week's candidate was Democrat Steven Horsford, running in Nevada's 4th District, who was accused by the National Republican Campaign Committee of, among other things, "selling private meetings with lawmakers in exchange for donations," which they sourced to a Las Vegas Review-Journal report.
On Wednesday, the National Republican Congressional Committee will launch a new attack on Rep. David Cicilline (D-R.I.), the likely winner of Tuesday night's Democratic primary in his district. He has been implicated in wrongdoing during his time as mayor of Providence, as he left the city in deep debt and may have purposely obscured his mismanagement of city funds.
The back-and-forth on ethics and corruption issues indicates that these could be potent in some of the closest races in the nation, where issues of character are capable of shifting support more than minor policy differences.