If he can't do this, the bill is as good as dead.
For those who forgot, this is what happened in the House earlier in the year. Conservative holdouts won concessions and eventually backed the bill that passed -- barely -- in May.
Now that the new bill is out, it's time for vote-counting and horse-trading -- and the pressure is on from President Donald Trump, who championed Republicans' health care efforts on Twitter Friday morning.
"Republicans Senators are working hard to get their failed ObamaCare replacement approved. I will be at my desk, pen in hand!" he tweeted, one of several messages he sent about health care.
What the moderates are worried about:
Medicaid, Medicaid, Medicaid
The revised Senate bill left Medicaid virtually untouched. Meaning the serious concerns that moderates have (particularly those in Medicaid expansion states) were not addressed. They don't like how quickly Medicaid expansion would be phased out under the bill, and also, how deep the cuts are to the program ($772 billion over 10 years).
The Cruz amendment
Moderates had expressed some serious concerns about the Cruz amendment, and yet, McConnell decided to include a version of it in the bill anyway. The gist of the concern is that the Cruz provision -- which would allow insurers offering Obamacare plans to also offer cheaper, bare-bones policies -- would weaken patient protections and send health care costs for the sick, including those with pre-existing conditions, skyrocketing.
Sign that it's all about the moderates?
Right after the all-GOP meeting in Thursday morning, McConnell huddled with a number of moderate Republicans in his office again. Centers for Medicare and Medicaid Services administrator Seema Verma was there, too.
Some of the attendees:
Shelley Moore Capito of West Virginia; Dean Heller of Nevada; Rob Portman of Ohio; Lisa Murkowski of Alaska.
Moderates did get some things that they liked
$45 billion in opioid treatment funding was important. Not enough, but still a favorable addition to the bill.
They also liked the $70 billion added to stability funds. But again, not enough to address all of their concerns.
Whip count: How close is this thing?
McConnell is potentially just ONE senator away from this bill going down on a motion to proceed vote.
The "no" votes right now: Rand Paul and Susan Collins. If one more person comes out against supporting a motion to proceed vote, the bill can't move forward.
A whole lot of undecideds: Murkowski; Jeff Flake; Heller; Rob Portman; Capito; Mike Lee; John Hoeven; Bill Cassidy; Thom Tillis; Ben Sasse; Thad Cocharn; Cory Gardner; Todd Young.
Timeline - when will they vote?
New Congressional Budget Office score early next week
Vote on motion to proceed mid-week
If that passes, then debate, vote-a-rama, followed by a vote on the bill.
Why CBO day will be so important
McConnell expects a new CBO score next week on the new underlying bill. The CBO score always can move opinions, and last time around, it did not help -- the non-partisan agency predicted that the Republican proposal would result in 22 million more people becoming uninsured by 2026 than under Obamacare. Some Republicans have expressed concern that a score on Cruz's amendment won't be finished by early next week, however. In that case, members may have to rely on analysis from HHS or OMB for the Cruz amendment.
Here's why that matters: The CBO is considered the gold standard. They are the non-partisan arbiter of numbers and relying on the Trump administration's numbers for the Cruz amendment could make some members uneasy. This is just something to watch for and is not at all a sure thing. But it is something members have expressed some concern about.
What about the conservatives?
The good news for McConnell
Cruz appears happy to have his amendment (or a version of it) included in the bill. Cruz's amendment would allow insurers to offer skimpier health care plans with less coverage than would be allowed under Obamacare. Some experts have warned that the amendment could loosen protections for people with pre-existing conditions.
But, Cruz has said the amendment is a must for him because it would lower premiums, and if it stays in the bill, Cruz will vote for the motion to proceed. Cruz is a big get for McConnell, but he's only the tip of the iceberg.
The bad news for McConnell
Fellow Kentucky Sen. Paul has said he won't support the motion to proceed. And Sen. Mike Lee, a Republican from Utah, is still undecided on whether he will support moving onto the bill. That's problematic.
Where is Donald Trump?
The President has been facing issues related to his son, Donald Jr., as well as two foreign trips in as many weeks. But health care isn't far from his mind. Speaking to reporters Wednesday night, Trump spoke about how difficult it has been to get something to his desk.
"I'd say the only thing more difficult than peace between Israel and the Palestinians is health care," Trump told reporters onboard Air Force One. "It's like this narrow road that's about a quarter of an inch wide."
"You get a couple here and you say, 'great,' and then you find out you just lost four over here. Health care is tough," he added.