With a single tweet, Arizona Gov. Doug Ducey on Monday nudged the U.S. Senate within striking distance of passing its last-ditch plan for repealing Obamacare, in a bill many analysts say is bad news for Arizonans' health care.

In the span of about one hour:

• Arizona Sen. John McCain, whose dramatic "no" vote killed an Affordable Care Act repeal in July, told a Capitol Hill reporter he might "reluctantly" vote for the new Graham-Cassidy repeal bill if Ducey's concerns were taken care of.

• Within minutes, Ducey apparently answered McCain's call by tweeting his support for Graham-Cassidy, labeling it the "best path forward to repeal and replace Obamacare."

Graham-Cassidy is the best path forward to repeal and replace Obamacare. I will continue to work with the Congress and the Administration to give states more fliexiblity and more options moving forward. Congress has 12 days to say "yes" to Graham-Cassidy. It's time for them to get the job done.

• Sen. Lindsey Graham, the "Graham" in Graham-Cassidy and one of McCain's closest friends, then hailed Ducey's support as a 'great day for federalism, bad day for Obamacare."

• Ducey's friend Vice President Mike Pence chimed in with his support:

By apparently flipping McCain's "no" to a "yes," Ducey may have brought the Senate within one vote of passing Graham-Cassidy, with Vice President Pence as a tie-breaking vote in the Senate.

A McCain flip-flop would be stunning.

On "Face the Nation" Sunday, McCain repeated his call for the Senate to return to regular order for hearing legislation:

"If I could just say again, the way to do this is have a bill, put it through the committee. We have Patty Murray and Lamar Alexander are doing fine - bring it to the floor. Have debate. Have amendments."

None of that has happened with Graham-Cassidy.

Arizona Sen. Jeff Flake, who voted "yes' on every repeal bill in the Senate, tweeted his support Sunday:

Like McCain, Flake has also called for a return to regular order in the Senate. It is one of the centerpieces of his new book "Conscience of a Conservative."

Ducey's reference to "12 days to say yes" alludes to the Senate deadline for passing a repeal with a simple majority. After Sept. 30, the Senate would need 60 votes to repeal ACA.

Several analyses rank Arizona as one of the states that would be hit hardest by Graham-Cassidy. About 600,000 Arizonans are covered through the Obamacare marketplace or the the Medicaid expansion.

It would repeal much of the ACA and convert Medicaid and Obamacare subsidies into block grants - lump sums of federal cash - controlled by the states.

Arizona's share of federal dollars would plunge by an estimated $1.6 billion by 2026.

Ducey has long favored "block granting" Arizona's Medicaid funding, arguing that the state knows better than the feds how to spend the money.

Under Graham-Cassidy, Ducey would be responsible for setting up the state's own health insurance marketplace.

States could also waive coverage of pre-existing conditions and many of the current essential health benefits covered buy ACA; and eliminate the ban on insurers charging higher premiums based on a person's health status.