LONDON: Many long-time Labour Party members were skeptical about Jeremy Corbyn’s leadership when he was chosen to head the party after a political career marked by appearances at peace marches and union rallies.

But with opinion polls showing the gap between Corbyn and Prime Minister Theresa May narrowing, the 68-year-old who campaigns for “the socialism of the 21st century” has begun to dream of running the country after this Thursday’s general election.

“Look, never underestimate anybody,” the softly-spoken Corbyn told ITV News recently, a smile breaking across his bearded face. Corbyn should know — after all, some bookmakers had him at 500-1 two years ago when he ran for the leadership of his party.

With the support of Labour’s union base, nearly three-quarters of Labour lawmakers backed a vote of no confidence in Corbyn last year after he was criticized for his perceived lackluster role in the referendum campaign. But he was convincingly re-elected to the leadership in a ballot of the broader membership.

Under Corbyn, Labour’s membership has risen sharply, with the young particularly enthused by his left-leaning policies, which include nationalyzing the rail system and raising taxes on the rich.

Corbyn’s political biography includes a lifetime of left-wing causes.

In recent years he has been a leader of the Stop the War Coalition, which campaigned against Britain’s involvement in Iraq and Afghanistan. At other times he called for Britain to ditch its nuclear arsenal. And during the troubles in Northern Ireland, he was sympathetic to Sinn Fein, the political wing of the IRA, which backed a united Ireland.

He was also a serial rebel against many of the policies pursued by Tony Blair’s Labour governments.

His activism has prompted some to question whether he will be able to operate within the confines of government.

“I think Jeremy Corbyn is a professional critic,” said Victoria Honeyman, an expert on the Labour Party at the University of Leeds. “He’s better at knowing what he doesn’t stand for than what he does stand for. He’s never been in the political mainstream.”

The election has brought a few changes, though. He recently upgraded his “look” and now dons navy suits and pressed white shirts with red ties rather than rumpled corduroy. Vogue magazine asked, “WHO is Jeremy Corbyn’s stylist?” The beard remains.

But somehow, he cannot move too far from his austere image. After all, this is a leader who makes jam for fun from fruit grown on a garden allotment — a plot he intends to keep even if he wins.

“I think there’s a need for everyone in life to balance what they do, however stressful or important their job is,” he told ITV. “Balance in life is very important.”