Washington (CNN) Senate Majority Leader Mitch McConnell -- the Senate's premier negotiator -- is finding himself in the exact same spot House Speaker Paul Ryan was in earlier this year.

Dogged by deep ideological schisms within his conference, McConnell postponed a vote to repeal and replace Obamacare until his party can find a way to come together.

But more days of negotiations may not make the problem any easier. When Ryan was looking for the solution, he could afford to lose nearly two dozen members. McConnell can only lose two.

It's not simply that members want more time to look over the bill or review it. There are significant divisions within the party over what a Republican health care plan should even look like.

Moderate Republicans -- many of whom come from states that have been better able to help low-income people get health care coverage because of Medicaid expansion -- are dubious of rolling back federal dollars for their states. Without the money, there is fear that vulnerable populations could find themselves once again unable to afford health care.

But conservatives believe that Republicans have an obligation to stay true to their campaign promise. The promise was not to repeal parts of Obamacare, but leave the basic infrastructure -- the market place, the subsidies, the federal enhanced dollars for Medicaid-- in place. They argue, the promise was to repeal the program "root and branch."

Here's more on what key Republicans are looking for:

Rob Portman (Ohio), Shelley Moore Capito (West Virginia) and Susan Collins (Maine): more opioid funding.

The Senate's health care bill included just a drop in the bucket -- $2 billion -- to tackle the opioid crisis. Capito and Portman had requested $45 billion. That shows just how far off their ask leadership was.

The idea all along has been that Republican leadership has more money to negotiate with if they need to. They could increase the funding as a way to sweeten the deal for moderates, but so far it's unclear exactly how much that funding will grow.

Sen. Dean Heller (Nevada), Shelley Moore Capito and Rob Portman: Return the Medicaid growth rate to Medical inflation

This ask is a bit in the weeds, but here it goes.

The Senate bill -- in 2025 -- would begin tying the growth rate for Medicaid funding to standard inflation (CPI-U) instead of the more generous medical inflation (CPI-M). Medical costs are growing faster right now than the cost of other goods so if you tie Medicaid funding to standard inflation it means over time states would get less many from the federal government. Moderates are deeply concerned about what that cut could mean for their states. Medicaid is expensive, and if the states start to receive less money from the feds, it ultimately means they either have to find the money elsewhere to make up the gap or they have to start cutting benefits. That violates the promise that moderates made to not "pull the rug out" from vulnerable populations.

From the beginning, moderates told leadership this was a non-starter, but it ultimately was included in the bill to woo conservatives like Pat Toomey of Pennsylvania.

Ted Cruz (Texas), Mike Lee (Utah), Rand Paul (Kentucky) and Ron Johnson (Wisconsin): More flexibility and fewer Obamacare regulations.

This is where the conservatives come in. In addition to wanting the opposite of what moderates want on Medicaid funding, conservatives are also negotiating with leadership to try to make sure that more Obamacare regulations are repealed.

They have several suggestions for doing this, but one of the ideas is to allow more insurance plans to be exempted from Obamacare regulations. The conservative argument is that in order to lower premiums, you have to free insurers from having to offer things like essential health benefits or community rating, one of the key protections for people with pre-existing conditions. Community rating bars people from being charged more based off their past medical history.

Moderates, of course, worry that rolling back something like "community rating" could hurt people with pre-existing conditions. They are against going that far.

Susan Collins and Lisa Murkowski (Alaska): Strip the provision that defunds Planned Parenthood

As if this wasn't already complicated enough, the two moderate Republicans are asking for leadership to take out a provision in that defunds Planned Parenthood for a year. They argue Planned Parenthood provides key services to women and shouldn't be defunded. But, of course, conservatives say that the Planned Parenthood defund must remain in the bill to get their support.

There is also pressure from the religious right to ensure that this provision stays in the bill. Without it, conservatives might vote against it.

Rand Paul: Get rid of the Obamacare subsidies

Paul continues to argue that Republicans shouldn't be spending money on what he calls another "entitlement." Paul is opposed to the subsidies in the Senate bill, which help low-income people buy health insurance and are more robust for low-income people than the ones in the House bill. Paul argues they are nothing more than "Obamacare lite."

He's pretty much out on his own on this one, but it's one of the reasons why this negotiation is so tough for McConnell. Every vote counts. Even those votes on the fringes.