An additional 16 million people would be uninsured by 2026 under a so-called “skinny repeal” measure Senate Republicans may be crafting, according to a Congressional Budget Office report requested by Senate Democrats. The analysis is of provisions that Senate Republicans have said might be in such a measure, but Republicans have not released the actual text.

The estimate evaluates a potential bill that would repeal the 2010 health law’s (PL 111-148 , PL 111-152) individual and employer mandates and medical device tax, as well as its prevention and public health and community health center funds. The Democrats’ interpretation of the GOP bill includes a provision to defund Planned Parenthood for one year. Democrats on the Finance and the Health, Education, Labor and Pensions committees asked for an analysis of selected provisions in the replacement plan measure that Senate Republicans had previously introduced.

After failing to garner enough support to advance either a replacement plan for the health law or to roll it back, GOP senators are considering advancing a smaller measure that would roll back parts of the law, such as the mandates and the levy on devices. Senators highlighted those provisions as options but have said this week they aren’t sure what exactly such a measure would look like. Several GOP senators said its main purpose is to serve as a means to convene a conference committee with the House, which passed a broad overhaul (HR 1628) of the law in May. The Senate is currently debating amendments to the House bill.

CBO told Senate Democrats that under their interpretation of what a proposal might include, premiums would be roughly 20 percent higher than under current law each year, according to a senior Democratic aide. Premium information was not spelled out in the CBO estimate.

Over 10 years, such a bill would save $130.2 billion dollars, according to the analysis.

The estimate came on the same day that a bipartisan group of governors — including Nevada GOP Gov. Brian Sandoval and Ohio GOP Gov. John Kasich — wrote a letter opposing a scaled-back repeal bill.

The Senate should “reject efforts to amend the bill into a ‘skinny repeal,’ which is expected to accelerate health plans leaving the individual market, increase premiums, and result in fewer Americans having access to coverage,” said the letter.

The Blue Cross and Blue Shield Association also released a statement expressing concerns about the potential repeal of the mandate that most Americans get coverage without changes to other rules in the law.

However, several senators, including Nevada GOP Sen. Dean Heller and Kentucky GOP Sen. Rand Paul, said positive things about the possibility of passing a scaled-back repeal version. Paul was favorable about the idea if the House would pass it in the same form.