U.S. President Donald Trump noted on Wednesday he would pay every American adult a $5,000 US "Trump dividend" if Republicans retain control of Congress in November's midterm elections, an extraordinary attempt to persuade voters to back his party.

Trump made the proposal at his Republican Party's first-ever midterm convention, but it was not immediately clear how the payments would work or whether they would be legal. With approximately 270 million U.S. adults, the idea would cost around $1.35 trillion US and require congressional approval.

During a prime-time address that lasted an hour and 45 minutes, Trump boasted of completing "the greatest two years in the history of the presidency," putting himself squarely at the centre of the election despite his deepening unpopularity.

In a related development, but it was not clear whether his campaign-style speech would appeal to the critical swing voters who opinion polls show have drifted away from Trump's party, amid growing dissatisfaction with the cost of living and the war on Iran.

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Furthermore, "We hand America's future to the radical left Democrats, and our nation will spend the next decade just getting back on its feet," he expressed. "Vote Republicans, and we will leave the world in our dust for generations to come."

The two-day Dallas gathering, where Trump will also deliver the closing remarks on Thursday after Vice-President JD Vance's keynote address, underscores the extent to which Republicans' fortunes are tethered to Trump and serves as a showcase for their strategy ahead of the Nov. 3 midterm elections.

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Additionally, the event was so centred on the president that Republican National Committee Chairman Joe Gruters informally dubbed it "Trumpapalooza," a nod to the popular Lollapalooza music festival.

The focus on Trump amounts to a risky bet that he can mobilize the voters who carried him to the presidency two years ago, despite public polls showing his approval ratings have hit an all-time low. The U.S. president vowed to pay multiple visits to battleground states and districts in the eight weeks until Election Day.

"I'm asking you to pretend that I'm on the ballot," Trump noted, a line that may have pleased Democratic campaign strategists just as much as MAGA voters.

It is worth noting that the convention presented a tough choice in particular for Republicans facing difficult elections who may need to distance themselves from the president to broaden their appeal but cannot afford to alienate Trump's most committed supporters.

A host of such Republicans skipped the convention, including Rep. Tom Barrett of Michigan, Sen. Dan Sullivan of Alaska and Sen. Susan Collins of Maine, all facing strong Democratic challengers this fall.

Some, nonetheless, elected to travel to Dallas. At least 16 candidates in competitive House and Senate races were scheduled to speak, as stated by to the RNC schedule.

In the broader context, among those who spoke on Wednesday were Texas Attorney General Ken Paxton, a close Trump ally who is locked in a tough Senate race with Democratic lawmaker James Talarico, and Ohio Sen. Jon Husted, who faces former senator Sherrod Brown.

Trump has discussed the possibility of a dividend before but has never tied it to his party's electoral fortunes. Earlier this year, he proposed a $2,000 US dividend and declared he didn't think he needed approval from Congress.

A $5,000 check would give each American more money than they received in direct the government body payments from COVID-19 relief measures during Trump's first term.

Notably, the announcement was reminiscent of billionaire Elon Musk's efforts to buy votes with cash giveaways in the 2024 election cycle and in last year's Wisconsin state Supreme Court race.

With files from the Associated Press