The main reason for that, according to the report, is that the Obama administration could likely use alternative funding sources -- aside from the discretionary spending that stops with a shutdown -- to fund things like the law's premium tax credits for people purchasing health coverage starting Oct. 1.
The White House has a variety of alternative sources -- leftover money from the last fiscal year, the mandatory public health funding created by the law, among others -- to draw from in the event of a shutdown. In fact, according to the CRS report, the administration is already using some of them because Congress hasn't appropriated discretionary funding for ACA implementation this year. So that will simply continue.
"It seems likely that the administration will continue to rely on alternative sources of funding to support ACA implementation activities," the CRS wrote.
The House will vote Friday on a government spending bill that defunds Obamacare. They want to permanently strip funding for the law. But Senate Majority Leader Harry Reid (D-NV) has already said the bill is "dead" in his chamber, and the White House has threatened to veto it. So the House GOP's end goal almost certainly isn't attainable.
The House bill does, however, increase the likelihood of a shutdown if congressional Republicans refuse to cave by the end of the month. But even if they take this fight to that extreme, they won't stop funding for the president's health care reform law, according to the CRS.
The report is below.