Still, Graham-Cassidy might have the Senate votes to move on. If reports are to be believed, it only needs a handful more "yes" votes to pass. John McCain's just released statement that he won't vote for Graham-Cassidy doesn't necessarily kill the bill because none of the other potential "no" votes feel like a lock.

Rand Paul voted for the last repeal bill after consistently threatening not to; Lisa Murkowski is reportedly being offered incentives for Alaska to vote yes; and Susan Collins has stayed mostly quiet, so far saying only that she's "leaning no." While McCain's statement makes the bill's chances of passing slimmer, we've learned time and again during this process that it's not over until it's over.

Why? First, funding changes fall partly along party lines. States like New York and California – those that expanded Medicaid – will lose funding but would have been unlikely to vote for the bill anyway. Meanwhile, states like Alabama would see additional funding. The bill relies on enough Republican Senators voting with their party, and enough Senators from "bubble states" seeing alleged gains, to win the support it needs.

Perhaps more to the point, this is the Republicans' self-imposed last chance to rid themselves of Obamacare. Of course, it isn't actually their last chance – even after September 30 they'll control both Houses of Congress and the presidency – but it's the last chance to pass it with a simple majority. And they've backed themselves into a corner with their base. The GOP was humiliated, sometimes by its own president, over the summer for its health care failures. Passing something, anything, at the eleventh hour would help the party save face and move on to other matters.

But there's danger in passing a bill that has had essentially no vetting. If the independent analyses of the bill are to believed, Graham-Cassidy will leave millions of Americans without health insurance.

Should Republicans start treating their health-care bills like health-care bills — focusing on health outcomes rather than solely on budgetary procedures — they would be better able to get the backing of the public, industry groups and crucial members of their own party.

Commentary by Jennifer Fitzgerald, the CEO and co-founder of PolicyGenius, an independent digital insurance company for consumers. Previously, she was a junior partner at McKinsey & Company where she advised Fortune 100 financial services companies on marketing and strategy. She is a graduate of Columbia Law School and Florida State University. Follow her on Twitter @jenlfitzgerald.

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