US President Donald Trump has capped opening night of the unusual Republican midterm convention by making the extraordinary pledge to pay every adult American $5,000 if his party retains its control of both chambers of Congress after November. The billionaire leader coupled his claim with a plea for his supporters to “pretend” he was on the ballot.

“If the Republicans win, you win with us and you get $5,000. It will be called the Trump dividend,” he told the convention in Dallas, as the party struggles in polls against the Democrats.

The proposal, which could cost at least $1 trillion, is seen financially and politically implausible. The president did not specify where the money would come from, citing only that “our country is making so much money.”

Trump also doubled down on his bet that he can help Republicans to defy opinion polls and retain both houses of Congress on November 3 and said, “I’m asking you to pretend that I’m on the ballot.”