AP estimate: 12.2 million have enrolled in Obamacare

The Associated Press count includes all 50 states and D.C. and is a 4 percent decrease in enrollment from last year. The Centers for Medicare and Medicaid Services released official enrollment numbers last week only for the 39 states using federal exchanges.

Of the 12.2 million, 64 percent live in states President Trump carried in last year's election.

Why this matters: These are the people who could have the most to lose if Republicans create chaos in the marketplace through their efforts to repeal and replace Obamacare. It underlines the political difficulty of delivering on their campaign promise without harming their own voters.