The number is also likely to go up. Major states like Ohio and Texas, where enrollment had not been finalized, were not included in the final tally.
"The Affordable Care Act is making it easier for low-income individuals to get health insurance, by simplifying the system and allowing them to fill out one application to find out if they qualify for Medicaid or tax credits for private health insurance," CMS spokeswoman Emma Sandoe said in a statement.
The findings suggest that many people are coming to the program outside of HealthCare.gov and the state websites. When HHS released those enrollment figures as of Nov. 2, about 400,000 had been found eligible for Medicaid through those marketplaces -- much lower than the 1.5 million found in the new report.
It's not clear what is driving increased enrollment outside of the Obamacare websites. But there is some evidence that the rollout of Obamacare has increased awareness of Medicaid availability in general. Officials in South Carolina, for example, said they believed heightened awareness was driving increased Medicaid enrollment there, even thought the state did not expand its Medicaid program.
CMS also detected an uptick in interest in the programs in October, particularly in states that expanded Medicaid. In those states, the number of applications increased by 16 percent compared to the monthly average in July to September. In states that didn't expand, the number also went up, though less so: 4 percent.
The full report is below.