Washington State (h/t ArcticStones):

Enrollments in private health plans on Healthplanfinder, the state’s online insurance marketplace, surged past 65,000 as applicants hustled to beat the Monday night deadline for coverage beginning Jan. 1, Washington Health Benefit Exchange officials reported Tuesday. Nearly 69,000 others have completed the enrollment process, but haven’t arranged payment, and another group of undetermined size has begun applications that are in varying stages of completion. ... As of Monday at midnight, about 100,800 people newly eligible for health insurance through the state’s expanded Medicaid program had signed up. Almost half of those were transferring from the now-discontinued Basic Health program or were presumed qualified for a federal assistance program for the disabled. An additional 47,500 enrollments were from those who previously qualified for Medicaid under the old rules — primarily children — but had not been signed up. And more than 88,000 people already covered by Medicaid renewed their eligibility.

For private enrollments, Washington is the only state that distinguishes between "enrolled but not paid yet" and "enrolled and first month's premium paid"; every other state, and the HHS, counts you as being enrolled even if you haven't actually paid yet, so that's the criteria I use, although I did separate out the other 69K on the spreadsheet. For Medicaid, I'm not counting the 88K since they were just renewals, but the 47.5K do count since they appear to fall into the category of people who were already qualified but didn't know about it until the ACA and the state exchange. In addition, as in several other states, another 47,000 people are being automatically transferred over to Medicaid proper from an existing state program; this is one of the "orange cells" on the spreadsheet. Also, h/t to sulthernao, who found the actual WA exchange source that gives the precise numbers.