LONDON — Having called an early election in an attempt to expand her party’s majority in Parliament, Prime Minister Theresa May is pitching her “strong and stable leadership” at a time when Britain confronts the formidable challenge of leaving the European Union.

But on Monday, Mrs. May found that carefully crafted image at risk, as she agreed to revisit a controversial proposal to put a hard cap on the assets that residents who receive long-term care at home may own. The proposal, widely derided as a “dementia tax,” raised such an uproar that Mrs. May was forced to beat a hasty retreat.

The proposal was introduced on Thursday as part of the governing Conservative Party’s election manifesto, which Mrs. May presented as a shift away from the party’s Thatcherite past toward a more communitarian, meritocratic vision that empowers Britons and their nation to compete and succeed in the global economy.

But the proposal would have required long-term care patients to forfeit all but 100,000 pounds (around $130,000) of their assets, including the value of their property.