Washington (United States) (AFP) - US President Donald Trump on Monday chose the backdrop of Washington’s Reflecting Pool – a landmark whose botched renovation symbolized the 80-year-old’s chaotic second term – to try and rally Republicans against a predicted Democratic win in the midterms.

“This is the last day before the midterm elections, the most important midterm I believe in our lifetime,” Trump said 26 minutes into a rambling speech which focused on his project to renovate monuments in the US capital, rather than inflation, the Iran war and other issues driving voters.

Polls show Democrats poised to seize the House of Representatives and within reach of the Senate in Tuesday’s vote – a shift that would impose the first real political constraints on the president since he took office nearly two years ago.

Americans are increasingly dissatisfied with the economy, while Trump’s own approval ratings have hit record lows.

But a tired-sounding Trump repeatedly veered in the speech to his passion for renovating the Reflecting Pool and other Washington landmarks.

“This project should be a project that unites all Americans,” Trump said.

The pool is one of the US capital’s historic stages, most famous as the setting for Martin Luther King’s “I Have a Dream” speech in 1963 from the steps of the adjacent Lincoln Memorial.

Trump said Sunday he picked the site “just to show how beautiful it is.” But his roughly $15 million renovation ran into repeated and embarrassing setbacks that he has blamed – without evidence – on saboteurs.

Trump has predicted victory in the midterms for his Republicans, but acknowledged that he could face a new reality in an interview released Monday by the New York Post’s Pod Force One podcast.

“I think we’re going to do great – but if we didn’t win, I veto everything,” he said. “I’ll be vetoing, vetoing. And then they’ll come along and we’ll probably make some deals along the way.”

Winning just the House would give Democrats voting power over the federal budget and control of committees able to investigate alleged corruption under Trump, the Epstein files and other explosive issues.

A Democratic Senate could also block Trump’s lifetime appointments to the courts, including the Supreme Court.

- ‘Ransack, rape and plunder’ -

Democrats geared up for final rallies in battleground states, including in Texas with James Talarico and in Kansas with Adam Hamilton – two star Senate candidates seeking major upsets. Kansas has not elected a Democratic senator in nearly a century and Texas is a deep Republican stronghold.

Even so, Democrats remain wary of predicting victory.

Democratic Senator Raphael Warnock told CNN that the mood was “nauseously optimistic.”

Republicans have run a scorched-earth campaign, painting Democrats as communists and branding Abdul El-Sayed, the Muslim Democratic Senate nominee in Michigan, a terrorist.

Democrats have faced late divisions of their own, with left-wing candidates at times clashing with the party establishment.

On Sunday, Democratic congresswoman Haley Stevens endorsed El-Sayed’s Republican opponent, Mike Rogers, in Michigan’s pivotal Senate race. Stevens lost a bruising primary to El-Sayed in August despite establishment backing.

- Senate in play -

While the House appears highly likely to turn Democratic, the battle for the Senate is far closer.

Democrats need a net gain of four seats to take control. To win, Democrats must flip seats in states that Trump carried by double digits two years ago.

Forecaster Decision Desk HQ has Democrats winning the Senate 52-48 and the House by a comfortable 241-194.

The final New York Times/Siena poll, released Sunday evening, showed Democrats leading in all seven of the most competitive Senate races, though five were within the margin of error.

Tuesday is election day, but a record 54 million people have already cast ballots.

The midterms have also drawn about $11 billion in advertising, with large chunks coming from individual mega-donors.

Elon Musk, the Trump ally who led the so-called DOGE drive to slash the federal government, has given nearly half a billion dollars to help elect Republicans.