Donald Trump’s approval ratings may be cratering but his Democrat rivals are showing few signs of being able to capitalise on their opponent’s multiple weaknesses.

Late last month, Jon Ossoff, a youthful Jewish candidate, failed to pull off a much-hoped for victory in suburban Atlanta — the kind of territory the party needs to win if it is to seize control of Congress next November — completing a string of defeats in special elections which appear to indicate that, however unhappy many voters are with the president, they are not yet sold on the Democrat alternative.

The defeat of Mr Ossoff’s centrist campaign fuelled the bitter debate within the party between those who argue that only the kind of left-wing populism preached by Senator Bernie Sanders during last year’s presidential primaries can return the Democrats to power, and those who warn that such a message risks alienating college-educated suburbanites whose votes came close to delivering Hillary Clinton the White House.

But as their party bickers over how to reassemble the winning coalition which twice brought Barack Obama victory, some of the former president’s men think they may have found the answer: Jason Kander, a Jewish former army veteran, who Politico magazine recently christened “the hottest star in Democratic politics”.

Last November, Mr Kander came close to seizing a Republican Senate seat in Missouri, a “red” state Mrs Clinton lost by some 19 points. The 36-year-old found national fame during the campaign when he responded to attacks on him by the gun lobby by recording an ad which showed him reassembling a rifle while blindfolded. It ended with Mr Kander, who served as an intelligence officer in Afghanistan, challenging his Republican opponent to do likewise.

Mr Kander’s narrow loss has sparked interest around the country and a string of invites to address local Democratic parties. His message — that he came close to victory without “pretending to be a Republican or hugging the middle” — has grassroots activists swooning. At the same time, his decision to launch a campaign, Let America Vote, to challenge Mr Trump’s widely criticised allegations of voter fraud — a pretext, says Mr Kander, for Republicans to pass laws which tighten rules and suppress turnout among Democrat-voting minorities and young people — has earned him further plaudits.

Inevitably, the media has noted both Mr Kander’s appearances in New Hampshire and Iowa — the first two states to vote in the presidential primaries — and his response to questions about whether he’s planning a run for the White House. “Politicians never say never to anything,” he artfully responded to one journalist, while emphasising his priority is his voting rights work.

Nonetheless, the buzz around Mr Kander is growing. Not only is former vice president Joe Biden reportedly a huge fan, but his name was the first to cross Mr Obama’s lips when he was asked to name the Democrats’ future leaders shortly before he left the White House.

Mr Obama’s former team appear to share their old boss’ enthusiasm. The board of Let America Vote is a who’s who of Obama-era West Wing staff, including former press secretary Josh Earnest; Dan Pfeiffer, a senior adviser to the president; and Jon Favreau, his chief speechwriter.

Sceptics note that, despite two terms in the state House of Representatives, Mr Kander has never held a higher office than Missouri secretary of state. Impressed Democrats respond that Mr Trump’s election ripped up the old rules of the game.

Perhaps a more appropriate comparison, though, is not with the scandal-ridden resident of the White House, but the man who now occupies the Elysée Palace.

Like Emmanuel Macron, Mr Kander is a clean-cut political novice who refuses to apologise for his progressive politics and is determined to take on and beat the populist right. Indeed, the eight times Mr Kander’s name has appeared on a ballot paper is still eight times more than Mr Macron’s had been on one before April this year.