Officials tell The Associated Press that a nonpartisan investigative report concludes that management failures by the Obama administration set the stage for the computer problems that paralyzed the HealthCare.gov website last fall.
The Government Accountability Office — the investigative agency of Congress — will report Thursday on its months-long investigation.
GAO said the administration kept changing marching orders for contractors who built the computerized sign-up system, creating widespread confusion and leading to tens of millions of dollars in additional costs.
Republican and Democratic congressional aides briefed on the report say it faults the Centers for Medicare and Medicaid Services for ineffective oversight.
CMS is the lead agency administering President Barack Obama's health care law.
The aides spoke on condition of anonymity to discuss the report ahead of its release.