Barack Obama told a Detroit crowd on Saturday that Abdul El-Sayed was “fighting for change, real change, that will get money out of politics and put money in your pocket”, as he threw his weight behind the Democratic Senate candidate and the rest of the ticket on the first day of early voting in Michigan.

Obama said in front of thousands of onlookers at Cass technical high school in Detroit that El-Sayed would “finish the job we started with the Affordable Care Act and guarantee quality, affordable healthcare to every single American”.

The former president headlined the rally for El-Sayed, the Democratic nominee for US Senate, and secretary of state Jocelyn Benson, the party’s candidate for governor, at an evening event to “get out the vote”.

He accused Donald Trump of “enriching himself and his family”, and said the administration had set a “culture … at the top” of taking favors. “Never seen a president so intent on selling favors like this,” he said.

The rally came on the first day of Michigan’s early voting period, with the general election on 3 November. It was also Obama’s first weekend of in-person campaigning during the midterms, which started in Cleveland, Ohio, earlier in the day to stump for the former Ohio senator Sherrod Brown and Democratic nominee for governor Amy Acton earlier in the weekend. He issued similarly scathing remarks aimed at the White House and the GOP.

The Detroit stop is Obama’s first public show of support for El-Sayed, who emerged from a bitter August primary in which the former president stayed on the sidelines. El-Sayed, a doctor and former Wayne county health official, beat the moderate congresswoman Haley Stevens who was riding on the backing of the Democratic establishment and pro-Israel organizations.

Obama was on the offensive against the administration, mocking the defense secretary, Pete Hegseth, as “laser-focused” on the “jawline and testosterone levels of our troops”, asking: “How much time do you think this man spends in front of the mirror every day?”

On tariffs, Obama said Trump was toughest on “that well-known evil empire”, referring to Canada, a few minutes’ drive from Detroit across the bridge. “These are the people who gave us Martin Short and maple syrup,” he said.

He even took a jab at Trump’s attempts to renovate the White House. “He should be on HGTV,” Obama said of the many renovations in Washington, including the White House ballroom and the Rose Garden. “He’s got the White House looking like Saddam Hussein opened a Cheesecake Factory.”

Questions had hung over whether Obama would back El-Sayed at all. El-Sayed, a champion of Medicare for All, had at one point called the Affordable Care Act, Obama’s signature domestic achievement, an incremental fix. The two men spoke by phone after the primary, and El-Sayed has since called Obama a mentor figure.

El-Sayed has the most ground to make up in Wayne county, where Detroit is the county seat, after Stevens beat him there by about 51% to 45% in the August primaries. Obama last campaigned in Detroit – which is more than three-quarters Black – in October 2024 for Kamala Harris, and Harris herself appeared with El-Sayed in Detroit last month.

Republicans have not held a Michigan Senate seat in 25 years, but the party sees the seat as one of its better pickup chances nationwide. El-Sayed faces Mike Rogers, a former congressman endorsed by Donald Trump who lost a 2024 Senate matchup against Democratic senator Elissa Slotkin by less than half a percentage point. The Cook Political Report rates this race a toss-up.

Slotkin, a featured speaker at the rally, told the crowd that “Michigan believes in electing fighters”. And when it came to any disagreements she may have with El-Sayed, she said: “It’s OK because we agree on so much more.”

“We’re putting a check and balance on Donald Trump in the White House,” she said.

A Marist poll of likely voters statewide conducted in mid-October put El-Sayed at 50% and Rogers at 48%, within the margin of error. RealClearPolitics’s average had El-Sayed ahead by about 2.6 points in a similar timeframe.

Trump has attacked El-Sayed throughout the campaign, calling him a “jihadist”, pointing to his middle name and alleging that he had ties to the Muslim Brotherhood, which El-Sayed strongly denies, and has created one of the most viral moments of the year. El-Sayed has also faced a barrage of criticism from the establishment wing of the Democratic party over his appearances with leftwing streamer Hasan Piker.

Trump is due in the state himself on Sunday, when he will hold a rally for Michigan Republicans in Port Huron, on the Canadian border. The city said it will be the first presidential visit to St Clair county.

If elected, El-Sayed would be the first Muslim and first Egyptian American in the US Senate. Benson faces the Republican congressman John James; a James win would make him Michigan’s first Black governor.

Turning to the disagreements between them, Obama acknowledged that some people had pointed out that El-Sayed “didn’t like some things you did as president”. “We are not going to agree on every detail of every issue,” he said. “You know who else doesn’t agree with everything I do? Michelle Obama.”

“We share those values of making sure everybody gets a fair shot in this society,” Obama said, “and that the system’s not just run for those at the top.”