Soon after arriving at an outdoor pep rally in Johns Creek for about 50 of his supporters, Jon Ossoff, the young Democrat vying to prize the Sixth District of Georgia from the Republicans in a special election on Tuesday, is grabbed by a woman anxious to show him a hand-painted sign being carried by a friend. It said ‘Vote your Ossoff’, and featured a drawing of a wide backside.

“I can't be seen with that one,” Mr Ossoff quipped, swiftly moving past the sign to shake hands with others in the crowd. It was a good-humoured brush-off and, in truth, after weeks of crisscrossing this large congressional district northeast of Atlanta that includes many of its wealthiest suburbs, he had seen variations on the sign a hundred times before.

Mr Ossoff, who looks younger than his 30 years, is widely expected to easily outpoll all 11 of the Republican candidates also running in a race triggered when the district’s sitting Congressman, Tom Price, was picked to join Donald Trump’s cabinet as Secretary of Health. However, he needs to take at least 50 per cent of the vote in this first round to avoid a run-off in June, when victory, with Republican support unified behind just one candidate, is likely to be tougher.

That he has got this far has surprised many, not least because the district, which he grew up in, has not had a Democrat representative in Washington since 1979. Helping to propel him has been a surge of money coming in from Democrats outside the state anxious to use this vote to give Mr Trump a bloody nose and put Republicans on notice that their majority in the House of Representatives will come under much broader attack in the mid-term elections next year.

It’s a rocket-rise that, inevitably, has drawn attacks against him far more troublesome than any cheeky signs drawn by his own supporters. His opponents and other Republican groups have variously called him the liberal patsy of national Democrats, questioned his youth and inexperience including by releasing video of him japing around in a Star Wars skit when he was a student and attacking him also for his daytime job as CEO of a Insight TWI, a documentary film-making company based in Britain that has Al Jazeera as a client as well as the likes of the BBC.

In an interview with The Independent, Mr Ossoff, who spent five years as a congressional aide on Capitol Hill with high-level security clearance, dismissed the attacks on his work with TWI. Founded in 1991, many of the company’s films have focused on Africa, including a documentary to accompany the feature film Blood Diamond for CNN. It has made two films for the BBC: Panorama: Addicted to Aid (2008) and Kony: Hunt for the World's Most Wanted (2012).

“I am proud of the work that the team and I have done exposing crime and corruption around the world,” he offered. “I think these predictable, partisan and fear-based attacks will be rejected by the voters of this district. I think it shows contempt for the voters of this district who are well informed and who can see through transparent attempts to scare them and divide us.”

“I think the voters are more intelligent than most folks in Washington imagine,” he went on. Mr Ossoff, who lives just outside the district – another detail his foes are latching onto – argues that it is precisely because of a sour taste left behind by the campaign of President Donald Trump last year that so many people are responding to his message today even in a district that has for so long been dominated by Republicans.

“There is so much grassroots energy, the atmosphere is electric right now,” he offered. “I think the presidential campaign was so divisive and so negative that folks are refreshed by a campaign that is based on a positive and substantive vision for our local economy, focused on shared values that bring people to take this opportunity to send fresh leadership to Washington.”

Not everyone is convinced. He has been accused of running a campaign fuelled by millions in donations coming from outside the state and of exaggerating the importance of his work while on Capitol Hill. “The guy himself just seems really weak to me, and I have some problems with his stories he tells about himself,” commented Fred Davis, a veteran Republican strategist who is advising the campaign of Dan Moody, a former state senator, who aims to top the Republican field and, he hopes, take on Mr Ossoff in June if a run-off becomes necessary.