John McCain votes no on the GOP's 'skinny repeal' healthcare bill early Friday morning. Screenshot/CNN The Senate burst into audible gasps when Republican Sen. John McCain of Arizona delivered the decisive, finishing blow to the GOP's "skinny repeal" healthcare bill early Friday morning when he became the 51st senator to vote against it.

Republican senators were seeking to pass the bill, which would have stripped a few essential elements of the Affordable Care Act, known as Obamacare, to establish a conference with the House and create a more robust bill.

On Thursday, McCain joined Republican Sens. Lindsey Graham of South Carolina and Ron Johnson of Wisconsin in a press conference in which they demanded the House not pass the exact text they would be voting to move forward. But they received no assurances from House Speaker Paul Ryan that the bill would never become law.

Graham and Johnson joined 47 Republican senators in voting for the bill. Republican Sens. Lisa Murkowski of Alaska and Susan Collins of Maine were against the bill from the onset. With all Democrats in opposition, that left McCain as the decisive vote. If he were to vote yes, Vice President Mike Pence would have cast the tie-breaking vote to advance the bill back to the House. If McCain voted against the legislation, it would die.

McCain, who returned to the Senate this week as he deals with brain cancer, voted against it.

Watch the moment when McCain gave his thumbs-down:

McCain released the following statement early Friday morning to explain his vote:

"From the beginning, I have believed that Obamacare should be repealed and replaced with a solution that increases competition, lowers costs, and improves care for the American people. The so-called 'skinny repeal' amendment the Senate voted on today would not accomplish those goals. While the amendment would have repealed some of Obamacare's most burdensome regulations, it offered no replacement to actually reform our health care system and deliver affordable, quality health care to our citizens. The Speaker's statement that the House would be 'willing' to go to conference does not ease my concern that this shell of a bill could be taken up and passed at any time."

"I've stated time and time again that one of the major failures of Obamacare was that it was rammed through Congress by Democrats on a strict-party line basis without a single Republican vote. We should not make the mistakes of the past that has led to Obamacare's collapse, including in my home state of Arizona where premiums are skyrocketing and health care providers are fleeing the marketplace. We must now return to the correct way of legislating and send the bill back to committee, hold hearings, receive input from both sides of aisle, heed the recommendations of nation's governors, and produce a bill that finally delivers affordable health care for the American people. We must do the hard work our citizens expect of us and deserve."