Guinta's chief of staff, Jay Ruais, would not answer questions about the campaign but said the congressman remains focused on his legislative work. (Ruais sent a fundraising email on Guinta's behalf Tuesday night.)
In a GOP primary, other Republicans say there's no doubt Guinta's campaign-finance woes would take center stage. For years, Democrats raised questions about the source of the $355,000 loan that Guinta's first congressional campaign reported in 2010, but he has continued to maintain that the contributions came from an account with his own money. Yet in May, Guinta signed a settlement with the FEC stating they weren't his own funds and agreeing to pay a penalty.
"The campaign would be the entire five-year saga of the FEC investigation and the fine," said New Hampshire GOP strategist Dave Carney. "It would be the only issue."
There is a chance, though, that aversion to Guinta could be split between challengers. Republicans in the district continue to mention BAE executive Rich Ashooh, who narrowly lost to Guinta in the 2010 Republican primary, as a potential candidate. Pam Tucker, the former deputy speaker of the New Hampshire House, reportedly is weighing a run herself.
In Washington, the National Republican Congressional Committee is continuing to stand by Guinta. But Republicans in New Hampshire, worried that Guinta's troubles could imperil their chances at the Senate and governor's races, have been less forgiving.
Sen. Kelly Ayotte, the state's most prominent Republican officeholder, has called on Guinta to step down, along with Republican leaders of the New Hampshire Senate and House. In a letter to the New Hampshire GOP's executive committee, Chairwoman Jennifer Horn said Guinta has "lied and betrayed the public trust," stopping short of directly calling for his resignation.
Since the FEC investigation came out, Guinta hasn't held any fundraisers in the district. On Saturday and Monday, he sent out his first fundraising emails since the scandal broke.
In one, he wrote, "Despite the progress we are making, Nancy Pelosi and top Democrats have made me a top target for 2016. They are planning on spending millions to try to beat me and take back the House in 2016."
Meanwhile, Democrats are watching the situation unfold, waiting to see if more information on the issue surfaces. A Democratic election law attorney has said Guinta's admission in the FEC settlement could open him to a criminal investigation.
"We're treading water," said Kathy Sullivan, a Democratic National committeewoman in New Hampshire. "People for the most part just really don't understand why he's sticking around."
The district has flipped back and forth between Guinta and Democrat Carol Shea-Porter in each of the last three elections, and Shea-Porter is expected to run again, according to state Democrats. In an email to supporters in late May, she said Guinta should resign and said she's "ready to win" the seat back. Businessman Shawn O'Connor, a Democrat, is Guinta's only declared opponent so far.