When the House passed its version of the American Health Care Act — the budget resolution intended to gut much the 2010 Affordable Care act or “Obamacare” — many, including some Republicans who decided to give their support to the bill at the last minute, assumed that the Senate would address some of its perceived shortcomings: too many people being priced out of coverage, loss of essential health benefits. However, if some in the Senate get their way, the version it votes on could see millions more people without insurance.

The Washington Post points out that some conservatives in the Senate working group that is crafting its version of the AHCA are making a push for changes that go even further than the House version in restricting Americans’ access to healthcare.

Sen. Ted Cruz of Texas has been given a prominent role in the 13-member GOP working group. This has surprised some, given Cruz’s previous outspoken disdain for the leadership of his own party.

With Cruz and his like-minded Sen. Mike Lee (UT) so heavily involved in these negotiations, there are early indications that the AHCA is being nudged further to the right, instead of the center.

While no drafts have been circulated yet, the Post notes that Cruz and the Senate conservatives have some likely targets, top among them being Medicaid. Some in the Senate believe that so-called “able-bodied” Medicaid recipients should be ineligible for coverage through the program. That would mean 11 million lower-income Americans having to find insurance or go without.

Then there are the tax credits proposed by the AHCA. Under the House version of the bill, individuals who don’t have insurance from their employer or the government would receive a tax credit of between $2,000 to $4,000 (depending on age and income, and capped at $14,000 per family). These tax credits are currently refundable, meaning that they can don’t just reduce the amount of tax you owe but could also be refunded to you if they reduce your overall tax liability to below zero.

The Post says that GOP conservatives want to make these credits non-refundable, meaning they can reduce your tax liability but can’t provide you with any cash beyond that. Their concern, apart from reducing government spending, is that these refunds could be used for medical services they find objectionable, like abortions.

However, making these credits non-refundable could negate their utility to lower-income Americans with minimal, if any, federal tax burdens. Someone who is already getting most, or all of their federal income tax refunded would likely not see any benefit from the tax credit.

Senate conservatives are also reportedly looking to make the most controversial aspect of the AHCA even more problematic. A last-minute amendment to the House version of the bill allowed states to opt out of certain Obamacare rules, like the one prohibiting insurance providers from charging higher rates to individuals based on pre-existing conditions.

According to the Post, conservatives would rather have these requirements repealed outright, or require that states opt in to accepting the rules, instead of the opt-out process suggested by the House.

Since the Obama administration, Cruz, Lee and have pushed for full repeal of the Affordable Care Act. Earlier this year, before the House introduced the AHCA, they were joined by Sen. Rand Paul of Kentucky in saying that the repeal effort should be just that: an actual undoing of the 2010 healthcare law. The problem for them is that the AHCA does not actually repeal that law.

For example, the so-called “individual mandate,” the requirement that most people purchase some sort of health insurance or face a penalty, still exists. The AHCA merely negates the effect of that mandate by reducing the financial penalty for non-compliance to $0.

What’s the reason for this sort of double-talk? The AHCA isn’t a traditional piece of legislation. It’s a budget resolution, meaning it only needs a simple majority in the Senate, as opposed to the usual 60 votes. In fact, the GOP only really needs 50 votes to pass this bill, since Vice President Mike Pence would cast the deciding vote.

The question that remains is whether any version of a Senate bill could get to 50 votes. Hard-line conservatives like Cruz, Lee, and Paul may not support legislation that doesn’t include additional cuts to Medicaid. However, making those cuts may drive away on-the-bubble moderates like Sen. Bill Cassidy (LA), and Sen. Susan Collins (ME).

There is also the issue of the Senate rules that limit what can actually be passed through the budget resolution process. In order to justify the simple majority vote, a budget resolution can’t increase the deficit in the long run and, perhaps more importantly, it can’t write new laws or drastically change existing ones.

Depending on how far conservatives go in trying to alter the Affordable Care Act, the Senate Parliamentarian may decide that the AHCA is no longer in line with the rules for a budget resolution. However, as Cruz recently pointed out, the Parliamentarian’s guidance is not the final say.

“The Parliamentarian merely advises, the Vice President decides,” Sen. Cruz explained. “Mike Pence is the ultimate decider.”