The last man to pull out of the Republican race against Donald Trump was John Kasich, the Ohio governor, a long-shot contender for the presidential nomination whose chances had long since faded. But he has returned to the role of thorn in Mr Trump’s side as Republicans in Washington struggle to reform Obamacare, leading a group of governors trashing their own party’s plan.

The intra-party revolt is rooted in Republican proposals to gut Medicaid, a programme for the poor that provides insurance to 69m Americans. Republicans have long seen it as an emblem of mismanaged welfare programmes that distend government and discourage people from working. But Mr Kasich is showing change is afoot.

He was one of 16 governors from Republican-led states that took an option to expand Medicaid offered by Obamacare, adding 700,000 Ohioans to the programme, despite the broad distaste for Barack Obama’s reforms in his party. In recent weeks he has stressed its vital role in treating people ravaged by opioids and other drugs, which killedan average of 11 Ohioans each day last year, and those suffering from schizophrenia, bipolar disorder and other mental illnesses.

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