With seven days to go until the midterms, Republicans and Democrats are locked into a seemingly endless tug-of-war, trying to focus voters’ minds on immigration and healthcare respectively, in a bid to rile up their bases. At this point in the campaign period, it’s about getting supporters to actually vote rather than winning over those who are uncertain.

Donald Trump did his worst by focusing on the caravan of Central American migrants travelling to the US-Mexican border, trying to dominate the media narrative by scaremongering and dog whistling, and even deploying more than 5,000 troops to the border in a transparent attempt to stoke further immigration fears with a disproportionate response. (By comparison, the US has around 2,000 troops deployed in Syria to combat Isis.)

But last week’s news of pipe bombs and the Pittsburgh synagogue shooting managed to put these campaign issues on the backburner, offering renewed hope that the Democrats will not only win control of the House of Representatives (latest forecasts give them an 85 per cent chance), but also gain a few senate seats in states that voted for Trump in the general election. In Texas, latest polls give Ted Cruz a narrow five-point margin over Democrat Beto O’Rourke, compared to his 9 per cent lead earlier this month, with 3 per cent of voters still undecided. In Tennessee, the race to replace Republican Bob Corker is hotting up as Democrat Phil Bredesen is winning over right-leaning voters, despite a Charles Koch-funded super PAC pouring millions into vicious ads attacking him. Democrat (although conservatively so) Joe Manchin is also safe in West Virginia – the state which gave Trump his highest margin in 2016.

US Midterms 2018: The five big questions

The Democrats’ chance of gaining control of the Senate is still minuscule, given that North Dakota’s Heidi Heitkamp and Missouri’s Claire McCaskill are almost certain to lose their seats, and Florida’s race is increasingly tight. But gains in Trump country show that voters are no longer as likely to be wooed by his divisive rhetoric.

However, the most important pre-midterm figures were released in a poll yesterday, which revealed that record number of 18- to 29-year-olds will be turning out to vote next Tuesday. At an estimated 40 per cent, in fact: double the number of people under 30 who turned out in the 2014 midterms. And 66 per cent of them will be supporting Democrats.

It’s not surprising that American millennials are leaning left. Many of the issues which have mobilised young people since Trump was elected are key Democratic policies: gun control, gender equality (including abortion law) and LGBTQ rights are a lot more important to the so-called “snowflake generation” than immigration policy and tax breaks for the wealthy.

Trump, as these young voters have witnessed, calls for more guns every time there is a mass shooting, has appointed accused sex offenders to office, promises to overturn Roe v Wade and is trying to remove the rights of trans people to even be recognised, let alone offering them equal protection. His lazy calculation that pushing a social agenda so conservative it makes even staunch Republicans feel uncomfortable will mobilise his base seems to have backfired.

The silent masses who voted for Trump at the presidential election did so for one simple reason: he said he would make them richer. He promised an increase in jobs that has never materialised (in fact, fewer jobs are being created under Trump than in the last six months of Obama’s presidency); he waxed lyrical about a tax reform which would help the lower and middle classes but ended up primarily benefiting corporate America; he sold protectionism as a solution to their economic woes when it turned out to be a disaster for the agriculture industry and business owners.

With no economic miracles left for Republican candidates to invent, the party has had to rely on its social policies to sell to the public. And the young people Trump had written off in his miscalculations are in the wings, are now listening, getting angry – and are expected to vote against what they see.

Support free-thinking journalism and subscribe to Independent Minds

The political mobilisation of young people has been gathering momentum throughout Trump’s presidency. The shooting at Stoneman Douglas High School spawned a new generation of anti-gun activists; the appointment of Brett Kavanaugh saw college protests, led by young politically active women, across the country; the victory of 28-year-old Alexandria Ocasio-Perez in the New York primary for House Representative earlier this year means she could become the country’s youngest woman ever elected to congress. Trump’s presidency has given us little to be thankful for, but a drastic increase in youth engagement in politics may be his one positive lasting legacy.

Support free-thinking journalism and attend Independent events

If young people really do turn out to vote in anything like the numbers predicted this week, not only will the Democrats sweep the House but they may even tip the scale of Senate forecasts – which, given the current 49-51 makeup, could be crucial.