Chris Pappas is stopping himself from getting too excited ahead of Tuesday’s midterm election.

“I take nothing for granted,” said the four-term US representative and Democratic nominee for New Hampshire’s open Senate seat. “This is a very purple, competitive state. Elections are never in the bag here.”

The race to replace the retiring Democratic senator Jeanne Shaheen has emerged as a source of 11th hour anxiety for the party.

In their attempt to gain four seats and reclaim control of the Senate, Democrats can’t afford to lose one they already hold. But September polling showing Pappas virtually tied with his Republican opponent, former senator John Sununu, rattled party strategists and raised the prospect that New Hampshire could become an unexpected battleground.

The warning signs were striking in a state Donald Trump has lost in each of his three presidential bids.

The blessing and curse of Trump’s shadow

While Pappas has regained a narrow advantage in most polls, and the Cook Political Report moved the race in early October from “toss-up” to “lean Democrat”, his closing message has focused heavily on tying Sununu to an unpopular president.

Trump’s approval rating sits at just 32% in the state, according to a recent University of New Hampshire poll, giving Democrats hope that voter frustration with the administration will ultimately benefit Pappas’s run.

“Sununu has spent most of the last year on team Trump, and now that we’re getting within range of the election, he’s recognizing how unpopular the president is,” Pappas said as he traveled the state in the final days on the trail, often joined by party heavyweights, like Arizona senator Mark Kelly and former vice-president Kamala Harris.

Democrats believe political headwinds facing Republicans have been strengthened by rising high gas prices and heating-oil costs linked to the war with Iran. More than a third of New Hampshire households rely on heating oil, and colder temperatures have pushed the issue to the forefront of voters’ minds ahead of election day.

“People are now starting to get really angry,” said Jim Demers, a veteran New Hampshire Democratic strategist. “I think a lot of people see Sununu as just one more Republican who will try to talk a good game, but when push comes to shove, he will not stand up to Trump because Republicans in Washington have a record of not doing it.”

For voters like Randy Marchand, who is supporting Pappas, but considers himself an independent, the Republican party is ultimately a rubber stamp for the president’s agenda. “I’m afraid for our democracy … right now the Republican party is no more,” said the 54-year-old flight attendant, who lives in Manchester. “They will say one thing to get in, and will ultimately come down to what Trump wants.”

Sununu, however, has spent much of the campaign arguing that independence, not loyalty, defines his political record.

The former senator has emphasized his criticism of Trump’s trade war with Canada, which has affected several industries in the state, and in a recent campaign advertisement, he even claimed to have “never met” the president.

The former senator’s anti-Trump bona fides do have some roots. In 2024, he voiced his support or Nikki Haley in an op-ed during Republican primary campaign, and also branded Trump a “loser”.

This week, during the final televised Senate debate, Pappas argued that Sununu initially backed the administration’s decision to launch strikes on Iran. Sununu countered that the congressman “exaggerates” his position and noted that he has consistently opposed putting American troops on the ground.

Democrats dismiss those distinctions as largely tactical. “Sununu has spent most of the last year on Team Trump, and you know now that we’re getting within range of the election, he’s recognizing how unpopular the president is,” Pappas said in an interview. (The Sununu campaign did not respond to the Guardian’s request for an interview.)

Sununu’s Trump problem is also causing consternation for some Republican operatives in the state.

While New Hampshire voters like “local Republican control”, it might “be a little too much to send Trump an additional senator when the president’s numbers are just so low. It’s very difficult to articulate why a Republican should win that seat,” said one New Hampshire strategist who spoke on the condition of anonymity to comment candidly on the race.

“The war in Iraq is what broke the back of the Republican party in New Hampshire 20 years ago,” the operative added, noting that Sununu’s support for the initial authorization contributed to his failed re-election bid in 2008. “Now we have a war in Iran, and while it’s asymmetric, it is economic. That psychological toll certainly doesn’t help.”

A history of ticket splitting

New Hampshire’s habit of ticket-splitting complicates any effort to view the Senate race solely through a national lens.

The state’s congressional delegation is all-Democratic, while Republicans control the state legislature and the governor’s office. In 2024, voters backed Kamala Harris for president while electing Republican Kelly Ayotte as governor.

This year, that same kind of mixed vote is prevalent throughout the state. John McAllister, a firefighter in Nashua, said that he and his association were supporting Pappas this election, while also backing Ayotte – who is leading the polls in her re-election race against Cinde Warmington.

Pappas has been a “true supporter” of firefighters’ issues “as long as he’s been in the House”, McAllister said. Meanwhile, Ayotte’s work on pension restoration for public safety employees in New Hampshire has put “thousands of dollars” back into first responders’ pockets, he said. As a result, a consistently blue or red vote is never guaranteed. “We have proven time and time again to go either Republican or Democrat,” McAllister said.

Two establishment figures fight it out

Unlike many of this year’s Senate contests, New Hampshire’s race pits two deeply familiar political brands against one another.

Pappas has represented the state’s first congressional district since 2019 and previously served on the executive council. His family also owns the Puritan Backroom restaurant, a fixture of New Hampshire political campaigning, and the alleged birthplace of the chicken tender. If Pappas wins this year’s election, he will be the first out gay man to serve in the US Senate.

Sununu, who served as a congressman before winning his upper-chamber seat in 2002, comes from one one of the Granite state’s best-known political dynasties. Both his father and younger brother, Chris, served as governor.

The latter even joked that he would be “up by 30 points” if voters thought he was running for Senate this year. Sununu responded by saying: “I love my brother but he’s totally wrong.” If he triumphs, Sununu would also be the first Republican senator that New Hampshire has sent to Washington since 2010.

In a national midterms cycle that is characterized by energy for insurgents and anti-establishment energy, the New Hampshire race appears to be an outlier. Two familiar names with robust records to scrutinize.

At their final televised debate this week, Sununu chided Pappas for his eight years in office where he “hasn’t gotten the job done” and accused him of siding with his party leadership too frequently.

But Pappas made sure to list the ways in which he has broken ranks when necessary and crossed the aisle, pointing to “yes” vote for the Laken Riley Act, the Republican-led legislation that requires the detention of undocumented immigrants charged with theft-related crimes, and his support for a congressional stock trading ban.

Meanwhile, Pappas targeted Sununu’s previous support to privatize social security when he was last in the Senate. “I’ve never voted to cut social security benefits, I never will,” Sununu said. “But Chris attacks me for introducing legislation 20 years ago that would have made the system solvent.”

The campaign has also occasionally veered into personal attacks. In September, Pappas referenced a 2010 email released as part of justice department files related to Jeffrey Epstein, in which the late sex offender wrote that “John Sununu has great stories” in a message to his associate Boris Nikolić.

The exchange followed attacks from national Republicans mocking a photograph of Pappas on a Zoom call with his cat. Pappas responded on social media: “I have a cat, and John Sununu’s name is in the Epstein files.”

It remains unclear whether Epstein was referring to the Republican nominee or his father, former governor John H Sununu. Earlier this year, Sununu’s campaign said neither man had “ever met or communicated in any way” with Epstein or Nikolić.

Looking ‘beyond the next two years’

Some Republicans argue that Democrats are betting too heavily on antipathy toward Trump to defeat a candidate they view as genuinely independent.

“As someone who is a fiscal conservative … and wants to make every penny count, Sununu is a brilliant guy, and he really cares about the bottom line,” said Kate Day, a 69-year-old retiree from Chesterfield. “He’ll let you know if he doesn’t agree with the rest of the Republicans. I think his number one job is going to be standing up for New Hampshire, which is how it should be.”

Republicans also contend that voters are evaluating the race through a longer lens than the remainder of Trump’s presidency. “[Voters] know that this is an election for the next six years,” said Joe Sweeney, a state representative and deputy majority leader in New Hampshire’s Republican-controlled house of representatives.

“I think that the Democrats have been in this pattern for the last 10 years, where every other word they talk about is about President Trump,” Sweeney added. “They have this sort of obsession with him, and I think New Hampshire voters are wiser than that.”

Some Republicans argue that Sununu would really be the state’s only opportunity to elect a stronger voice to check Trump in his final years in office.

“If you really want to modify what the president’s doing, you need someone in his own party fighting back, not someone who’s going to be a rubber stamp,” said David Carney, a longtime New Hampshire Republican strategist, pointing to senators such as Susan Collins of Maine and Lisa Murkowski of Alaska.

Yet even Carney acknowledged the challenge facing Sununu in a state where Trump remains deeply unpopular.

“We’re not immune in New Hampshire from the national environment,” he said. “We get influenced by what we see and what we feel is happening across the country.”