No longer an also-ran, British opposition leader hits campaign trail

(Repeats story sent on Aug. 22, no changes to text)

* Labour made gains in June, Conservatives lost majority

* Corbyn hopes for early election, orders summer campaign

* Opinion polls show improvement for Corbyn and Labour

* Some banks now take Corbyn challenge more seriously

By Emma Rumney

REDRUTH, England, Aug 22 (Reuters) - British opposition leader Jeremy Corbyn is back on the campaign trail just weeks after losing an election, betting that Prime Minister Theresa May's minority government will soon collapse.

Long written off by opponents and many members of his Labour Party as an old-fashioned socialist incapable of winning power, Corbyn has been galvanized by the June election, in which Labour made gains and May's Conservatives lost their majority.

With May's authority severely dented and the Conservatives struggling to unite over Brexit, he has ordered his party to hit the campaign trail as other parties spend the summer regrouping.

There is no sign yet that Corbyn will get the early election he is betting on. But business leaders who once wrote him off now take his challenge seriously and former Prime Minister Tony Blair, a big critic, says Corbyn could one day lead Britain.

"This government thinks it is there for some time to come," Corbyn, 68, told hundreds of people at a rally this month in Pool, a village outside Redruth, a former mining town in a deprived area of southwestern England.

"I've got news for them: we are touring the whole country this summer," he said at the site of a former mine.

Seeking a head-start if there is a new election, Labour has identified 100 constituencies in England, Scotland and Wales which it believes it can win from the Conservatives, including seats held by lawmakers such as Foreign Secretary Boris Johnson.

Corbyn, who plans to visit about 50 of the target areas himself, has been wooing the crowds by attacking the Conservatives over cutbacks in public services and denouncing a political system which he says favours the rich.

"It's the largest campaign Labour has ever embarked upon outside of a general election in the modern era," said Ian Lavery, Party Chair and National Campaign co-coordinator.

"We want to build on the campaigning momentum from the general election to build support in marginal constituencies to take us into government."

GRASSROOTS CAMPAIGN

To be sure, the next election is not due until 2022, and the Conservatives will do all they can to ensure they do not gift Corbyn a chance to win power.

The most likely cause of a new election would be the government being torn apart by divisions over Brexit or the Conservatives deposing May, who has to rely on a small Northern Irish party to ensure she can pass legislation.