Daniel Radcliffe has endorsed Jeremy Corbyn to win the Labour leadership contest on Saturday, saying the left-wing MP reminded him of a favourite teacher from school.

The Horns actor told the Big Issue magazine Corbyn had won him over with an interview where he talked about his allotment and making jam. “He reminds me in the loveliest way of my English teacher," said Radcliffe, “who is someone I am very, very fond of – so he has a fast track to my heart!”

The 26-year-old praised the Corbyn for galvanising young voters and the disenchanted with his sincerity and conviction, describing the effect he has had on Labour party supporters as “incredible”.

“It is just so nice to have people excited about somebody," he said. "It seems to be more or less because they are excited about sincerity. I think we all suddenly realised that we are so used to politicians lying. Even when they are being sincere, it feels so scripted that it is hard to get behind them.”

Labour leadership: The Contenders Show all 4 1 /4 Labour leadership: The Contenders Labour leadership: The Contenders Jeremy Corbyn Jeremy Corbyn readily admits he is only standing to ensure the left of the party is given a voice in a contest dominated by candidates promising to move the party towards the centre-ground of British politics Profiles by Matt Dathan BBC Labour leadership: The Contenders Andy Burnham Andy Burnham is the current front-runner to win the leadership election according to bookmakers, but the fact that the Conservative party leadership hopes he wins shows the task that awaits if he is Ed Miliband’s successor. He will have to find a way of distancing himself from both the last five years under Mr Miliband and the Blair and Brown years, during which he served in the Cabinet Jon Super Labour leadership: The Contenders Yvette Cooper Yvette Cooper will also face a battle in convincing voters she offers a sufficient break with the past, having served in Gordon Brown’s Cabinet and she played a key role in Mr Miliband’s team as shadow home secretary. The fact that her husband is Ed Balls will not have a negative impact internally but voters are not likely to look favourably on the prospect of Mr Miliband’s ousted shadow chancellor entering Downing Street if Ms Cooper wins in 2020 Getty Images Labour leadership: The Contenders Liz Kendall Liz Kendall faces criticism over her lack of experience – she was only elected in 2010 and has no experience of serving in government and wasn't even in Ed Miliband’s shadow cabinet. But that very lack of experience means she can make a pitch as the only candidate offering real change and a real break from the Blair/Brown/Miliband years Getty Images

Corbyn reluctantly entered the leadership race almost 100 days ago because it was “his turn” and was only nominated by some of his peers to make the process more democratic. But he quickly emerged as the unexpected frontrunner in the race, winning over Labour supporters across the country with his clear and unwavering policies on immigration, austerity, nuclear weapons and a number of other contentious issues.

The extent of his support was demonstrated at a packed homecoming rally for the MP for Islington North on Thursday evening, where he was met with rapturous applause.