(AFP) - Republican hopes for a sweeping rebuke of President Joe Biden in congressional elections failed to materialize with both parties picking up seats following a campaign fought against a backdrop of stubbornly high inflation and fears for US democracy.

Republicans needed one seat to wrest control of the evenly-divided Senate but by early Wednesday the only one to change party hands went to the Democrats, with John Fetterman, a burly champion of progressive economic policies, triumphing in Pennsylvania.

In the House of Representatives, early results suggested Republicans were on track to wrest control from Democrats -- but only by a handful of seats, a far cry from their predictions.

Top Republican Kevin McCarthy -- who hopes to be the lower chamber's next speaker -- struck an upbeat note as he addressed supporters in the early hours, telling them: "It is clear that we are going to take the House back."

But Senator Lindsey Graham, a top Trump ally, bluntly conceded to NBC that the election is "definitely not a Republican wave, that's for darn sure."

With Biden's favorability ratings hovering in the low 40s and Republicans pounding him over inflation and crime, many pundits had predicted a drubbing that would have raised new questions on whether America's oldest-ever president, who turns 80 this month, should run again.

The president's party has traditionally lost seats in midterm elections -- and all eyes have been on a handful of Senate races including in Georgia, Nevada, Arizona and Wisconsin.

In Pennsylvania -- one of the election's highest-profile races -- Fetterman limited campaign appearances as he recovered from a stroke that impeded his speech but he still edged out Mehmet Oz, a celebrity doctor endorsed by Donald Trump.

"This campaign has always been about fighting for everyone who's ever been got knocked down that ever got back up," the two-meter (six-foot-eight) Fetterman, clad in his trademark hoodie, told a rally in Pittsburgh.

- Florida swings right -

On a night of close contests, one of the most decisive wins was for rising Republican star Ron DeSantis, who won by a crushing margin in Florida, cementing his status as a top potential White House candidate in 2024.

DeSantis, who has made a name in Florida by railing against Covid mitigation measures and transgender rights, was projected to have won by up to 20 points against a folksy former governor, four years after squeaking by in his longtime swing state.

"We will never, ever surrender to the woke mob," DeSantis told a victory rally, using a derisive term for social justice campaigners.

"Florida is where woke goes to die," he said.

But if the 44-year-old views his victory as a mandate for the White House in 2024, he will likely face a stiff challenge from another Florida resident -- former president Trump, who has teased an "exciting" announcement on November 15.

Among other races, Maura Healey will make history as the first openly lesbian governor in the United States and in New York, where recent polls gave Democrats a scare, Governor Kathy Hochul fended off a Republican challenge.

- Trump again alleges fraud -

Trump, who is facing criminal probes over taking top secret documents from the White House and trying to overturn the 2020 election, returned to his playbook of airing unsubstantiated claims of fraud.

In Arizona, Trump and his chosen candidate for governor, Kari Lake, alleged irregularities after problems with voting machines.

Officials in the most populous county of Maricopa said about 20 percent of the 223 polling stations experienced difficulties related to printers but that no one was denied the right to vote.

Biden has warned that Republicans pose a dire threat to democracy with more than half their candidates repeating Trump's debunked claims of cheating in the 2020 election.

In the runup to the vote, an intruder espousing far-right beliefs broke into the San Francisco home of House Speaker Nancy Pelosi and bludgeoned her husband with a hammer.

In his closing pitch, Biden vowed that Democrats would defend pensions, health care and the freedom to have an abortion, after a Supreme Court transformed by Trump rescinded the right to choose.

Voting in Phoenix, Kenneth Bellows, a 32-year-old law student, said runaway inflation is "hurting Americans who are just trying to get by."

"We don't need any of the crazy woke rhetoric that's going on right now. What we really need is focusing on everyday kitchen-table politics, to make sure taxes are low," he said.

But at a restaurant serving up soul food in Pittsburgh, Lasaine Latimore, 77, said Democrats were best placed to help people.

"I just want my medical insurance and more money for dental and glasses," she said.

A Republican victory could scuttle Biden's legislative agenda, with Congress scuttling his ambitions on climate change and scrutinizing the billions of US dollars to help Ukraine fight Russia.

© Agence France-Presse