Watch: John McCain Votes No On Health Care Reform, Senate Gasps

WASHINGTON, DC — Sen. John McCain, still recovering from surgery and coping with a recent diagnosis of an aggressive brain cancer, stunned observers around the country early Friday morning when he cast the decisive vote against GOP efforts to repeal parts of Obamacare. In video embedded below, you can hear the Senate audibly gasp as the Arizona Republican turns his thumb down, bucking most his party's leadership and the White House.

In addition to Sen. Lisa Murkowski of Alaska and Sen. Susan Collins of Maine, McCain was one of only three Republicans to vote against the measure introduced under the cover of darkness. The bill's main provision would have eliminated Obamacare's mandate that most American adults either buy health insurance or face a tax penalty. It is one of the least popular parts of the law, but many health care experts say it's a necessary component to keep insurance premiums under control.

Others in the party were highly skeptical of the legislation; some even demanded a guarantee that the House would not pass the same bill as a precondition for their votes.

Watch McCain's stunning moment here:

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