With a rematch set between Joe Biden and Donald Trump after both candidates crossed the delegate threshold needed to clinch their parties’ presidential nominations, suspense around the next wave of Tuesday primaries shifts to a handful of key down-ballot races.

Five states – Arizona, Florida, Illinois, Kansas and Ohio – will hold their presidential nominating contests on Tuesday. Trump and Biden are expected to sail to victory, growing their delegate counts in a march toward this summer’s conventions, where they will officially secure their parties’ nomination.

Trump’s last Republican challenger, his former UN ambassador Nikki Haley, ended her presidential campaign after being routed on Super Tuesday, while the Democratic congressman Dean Phillips dropped his long-shot challenge to Biden after failing to win a single delegate, including in his home state of Minnesota.

In Florida, the state Democratic party decided support for Biden was strong enough and cancelled its presidential primary. Republicans in the one-time swing state can vote for Trump, though his vanquished rivals, including the governor, Ron DeSantis, will still appear on the ballot. The result may reveal clues about the enduring strength of the anti-Trump vote within the Republican party.

At a polling site in south Florida, Sue Griffiths said she voted for Haley, partly in case anything prevented Trump from being the eventual Republican nominee, but mostly in protest of the former president.

“There’s no way I could vote for him, and although I know this primary already seems to be decided, I just wanted my voice heard,” she said.

In this corner of the state, with no parallel municipal elections, ambivalence toward the foregone presidential primary was evident.

None of almost 1,500 registered Republicans had shown up to vote at their designated center at Taravella high school in Coral Springs more than two hours after poll workers opened it in a rainstorm.

At the nearby Sartory senior center, where 1,200 Republican voters are registered, a far bigger draw was the gentle fitness class taking place in an adjoining hall. The 10 poll workers staffing the site far outnumbered the trickle of those who came in to cast a ballot.

“Regardless if it’s up and down, or maybe you wanted to make a protest, it’s important that everyone who can take advantage of being able to vote should come and do it,” said Anthony Mineo, who showed up at the polls on Tuesday to vote for Trump.

Further down the ballot, meanwhile there could be some surprises in store on Tuesday.

Ohio

Ohio Republicans will choose their nominee in one of the most highly anticipated Senate races of the cycle. The heated three-way battle to take on the Democratic incumbent, Senator Sherrod Brown, features Republicans Frank LaRose, Matt Dolan and the Trump-backed Bernie Moreno. The final days have become increasingly bitter.

Trump held a rally for Moreno in Ohio this weekend, a day after the candidate, who has taken virulently anti-LGBTQ+ positions, was the subject of reporting by the Associated Press that his work email had been used to create an account on an adult website seeking “men for 1-on-1 sex” in 2008. Moreno’s team has condemned the report, and his lawyer told the AP that the account was created by a former intern as “part of a juvenile prank”.

During his speech, Trump defended Moreno, used dehumanizing language to describe immigrants and warned darkly that if he loses “I don’t think you’re going to have another election in this country.”

Ohio, once a perennial swing state, is now soundly Republican and backed Trump in 2016 and 2020.

Meanwhile, voters in eastern Ohio will choose their party’s nominee to represent them in a June special election to serve the remaining term of the seat vacated by Congressman Bill Johnson, a Republican who retired earlier this year to become a college president.

The leading Republican candidates will be on the ballot twice: once for the special election and again to represent their party in the November general election contest for this Republican-leaning seat.

In another closely watched primary, Republicans are vying for the nomination to challenge the longtime Democratic congresswoman Marcy Kaptur. State representative Derek Merrin has secured the backing of the party and his former Republican rival, the scandal-plagued JR Majewski, who bowed out of the race after disparaging athletes at the Special Olympics.

Illinois

In Illinois, the incumbent Democratic congressman Danny Davis is in the fight of his political life as he seeks to fend off a progressive challenge. But the 82-year-old, 14-term congressman, backed by the state’s governor, JB Pritzker and the Chicago mayor, Brandon Johnson, is also contending with calls for a generational change in leadership that echoes the concerns Democrats have with Biden.

California

Meanwhile, California will hold a special election to replace the Republican Kevin McCarthy, who resigned from Congress last year after his historic removal as speaker of the House.

McCarthy’s departure left Republicans with one less vote in the House, where their grip on the majority is already razor thin. The race for the seat, a rare conservative stronghold in the otherwise liberal state, will feature Republicans Vince Fong, a state assemblymember and McCarthy’s chosen successor, and the Tulare county sheriff, Mike Boudreaux.

While Fong, who won Trump’s endorsement, is favored to win the election to serve the rest of McCarthy’s unexpired term, it is possible he could be forced to a May runoff if no candidate secures a majority of the vote. The Republicans will face each other in the November general election for a new congressional term.

Elsewhere in the west, Biden will visit Arizona on election day, touching down in Phoenix after a stop in Nevada and before departing for events in Texas. Biden narrowly won Arizona in 2020 but polls show him trailing Trump amid deep dissatisfaction with his handling of the economy and border security.

As part of the Democratic effort to protest Biden’s handling of the Israel-Hamas war, organizers with the “Vote Ceasefire AZ” campaign are urging supporters to cast a ballot for the president’s nominal challenger, the self-help guru Marianne Williamson who recently “unsuspended” her presidential campaign. Williamson, who is one of several candidates to appear on Arizona’s Democratic primary ballot, has called for a ceasefire in Gaza and has advocated a “peace” department as part of her platform.

For observers closely tracking the strength of the “uncommitted” campaign, the result may be hard to parse. Unlike in Michigan and Minnesota, there are few options on Tuesday for Democrats upset with the president’s handling of the Israel-Hamas war to register their discontent at the ballot box.

Florida, for example, isn’t holding a Democratic primary. And Williamson won’t appear on the ballot in Ohio, where ceasefire activists there are urging supporters to “Leave It Blank”.

Biden v Trump: What’s in store for the US and the world?

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