In a stinging blow to President Donald Trump, U.S. Senate Republicans failed on Friday (July 28) to dismantle Obamacare, falling short on a major campaign promise and perhaps ending a seven-year quest by their party to gut the health care law.

Voting in the early hours, three Republican senators, John McCain, Susan Collins and Lisa Murkowski, crossed party lines to join Democrats in a dramatic 49-to-51 vote to reject a “skinny repeal” bill that would have killed some parts of Obamacare.

The setback leaves Trump without a major legislative win after more than six months in power, despite Republicans controlling the White House, Senate and House. It will also be a let-down for financial markets, which expected Trump to make rapid changes to health care, taxes and infrastructure spending.

The Affordable Care Act, approved by Democrats in 2010, is former Democratic President Barack Obama’s signature domestic achievement. It provided health insurance to millions of previously uninsured Americans.