In the battleground state of Maine, Todd Cox, 63, has supported the state’s incumbent Republican senator Susan Collins not once, but twice, in previous elections. Not this time.

On Tuesday, Cox, a technology professional, cast his vote for Collins’ Democratic challenger Troy Jackson – driven not by pressing local issues, but broader concern “for the direction the country is going in”, he said.

“We definitely haven’t become kinder and gentler under this administration,” Cox told the Guardian. “There’s a lot of bullying that goes on. It goes back to affordability. It’s the war in Iran – that shouldn’t be happening. It’s the disregard for the rule of law. It just seems like they’re thumbing their nose at it.”

As millions lined up to cast their ballots nationwide, the question looming over Tuesday’s US midterm elections – with control of US Congress and key checks and balances on Donald Trump at stake – was just how many Americans felt the same way.

There were signs of high turnout in this election, with 435 seats in the House of Representatives, 35 of 100 seats in the Senate, 39 governorships and thousands of state legislative seats up for grabs, as well as many local contests and ballot measures on issues including taxes, abortion rights and voting rules.

To win control of the US Senate in Washington, Democrats must flip four Republican-held seats and retain all of those currently held by the party. They meanwhile need a net gain of just three seats to obtain a majority in the House.

In interviews with the Guardian across the country, voters cited affordability concerns, Trump’s war on Iran and his administration’s aggressive crackdown on immigration as among the key issues that had driven them to cast their votes. Lines formed outside polling stations in key states including Texas and Maine.

In Maine, a steady stream of voters entered the Merrill auditorium polling station in Portland’s busy downtown district in mid-morning, leading to queues of up to half an hour to cast a ballot, according to organizers.

“I’m concerned about ICE raids that have been happening here in Portland,” said Maple Razsa, 55, a global studies professor at Colby College in Waterville. “The political system is just run amok at this point.”

There was still robust support for Trump’s party, however. “I voted straight Republican,” said a 63-year-man in Maine, who declined to give his name. “I don’t know much about the issues, but I’m not ready to throw away Israel yet. I don’t really see the war in Iran as a real war. What have we lost? Dozens. We lose hundreds and thousands in these wars and if they have a nuclear bomb, we’re going to have a nuclear war anyway.”

In Georgia, where heated races for the Senate and governor are playing out, David Boy, an attorney from Johns Creek, voted for Republicans yesterday despite his staunch antipathy for the president. “I don’t like Trump. I’ve never voted for him,” he told the Guardian. “I want to go to my deathbed saying I never did.”

But these are midterm elections – not presidential – and he looked beyond his view of the current occupant of the White House in a bid to elect candidates he believed would act on the issues he cared about.

“I’ve got school-age kids, so making sure the schools are good for them,” said Boy. “Taxes. I’m in the prime earning years right now, so paying taxes … and then also for me, personally, my faith and integrity and moral issues. And then, I want things to be run well. Honestly, I want our government to be run efficiently and effectively.”

These remain divided times. Jason Griffin, an engineer from Johns Creek, Georgia, told the Guardian he was specifically motivated to vote for Democrats on Tuesday by Trump. “I used to like the policies of most of the Republicans,” he said.

Others were driven by local concerns. “Michigan is in a dumpster fire,” Sona, a Dearborn resident in her 60s who declined to give her last name, said of another key swing state that both parties have chased on the path to controlling the Senate. She voted Republican.

Sona described herself as a lifelong conservative who opposes abortion and is concerned about “transgenderism”, specifically transgender athletes in women’s sports – an issue Republicans have sought to hammer in recent months. She also pointed to wages she said run about $10,000 below those in neighboring states, and to high electric bills.

In Alaska, another battleground state, Republican voter John House had a mixed assessment of Trump. “He talks too much, but he’s done so much for us,” he told the Guardian. But House, 62, a carpenter living and working in Anchorage, had no time for the Democrats. “You’d be a damn fool to vote Democrat,” he declared. “We’ll go backwards.”

Many voters took a different view. Chaunice Carr, 27, cast her vote for Mary Peltola, the Democratic senate candidate in Alaska – an action she described as “insanely important” to her. “There are a lot of bad things happening in Alaska, in the world. A lot of violence. ICE raids, people being deported in horrid ways. I’m hoping that today we can start to get that violence out of our lives.”

Juanita Cupa, also voted for Peltola. Prices are up, and life is tough. She spends $120 every two weeks filling up her truck, which she can’t do without in Alaska’s snowy wilderness. She is so hard up that she has had to move back in with her parents. “I’m living check to check.”

She was no fan of Trump, either. “He is spreading hatred, racism,” said Cupa, 30. “His leadership is disgusting – the way he talks about women, and human life.”

Alaska has been roiled in recent days by a report Peltola’s that campaign was behind an effort to recruit another candidate on the ballot called Dan Sullivan, with the same name as her Republican opponent. Peltola has denied any knowledge of such a scheme on the part of her campaign.

“It’s just been a lot of foolishness around this, on both sides,” said Cupa, with a weary shrug. “We’re all ready for it to be over.”