Mayor Michael Bloomberg says it was the financial crisis – and the billionaire businessman’s unique ability to take the city through it – that compelled him to try to change the law so he could stay in charge.

But advisers acknowledge he had long been considering a third act in office after his independent presidential hopes died.

He got his wish on Thursday when a divided City Council voted 29-22 to change term-limits law, allowing him another campaign for a four-year term. But Bloomberg was derided with calls of “Shame” and “Sellout!” as he left City Hall, demonstrating how thorny an issue this has become for the mayor.