Civis Analytics, a data analysis firm based in Chicago, was founded by alumni of the Obama campaign, who spent years figuring out how to find specific voters – and convince them to vote for Barack Obama.

Now, some of their analysts have turned their number-crunching skills to Obamacare and created one of the most detailed maps of where the uninsured live. The idea was to give the people doing enrollment a better sense of where, exactly, to focus their efforts.

"We came to this because it is a big and difficult problem," says Kate Jordan, engagement manager at Civis. "There are a lot of people who want to enroll individuals, but it's a small percentage of the population, about 15 to 16 percent nationally, and you have limited time and resources. How do you decide whose door to knock on, or where is it best to have your community events?"

Civis's map has an uninsured rate for each census tract, which usually includes about 1,000 or so people. This is a pretty granular level of detail: There are over 70,000 census tracts across the country, usually about the size of one neighborhood. The District of Columbia alone is divided into 179 different jurisdictions. And here's what the city looks like, when you break it down by the uninsured rate of each jurisdiction:

If you're doing outreach around the District of Columbia, the specific census tracts in Prince George's County immediately stand out as the places to head to. There are also small pockets in Northern Virginia, which typically has a high insured rate, that actually have lots of people without coverage.

Here are what a few other cities look like, starting with Baltimore:



Los Angeles:


And Chicago's South Side, up close:

You can play around with the full map here. Civis is now working to distribute the tool to smaller community groups doing health law outreach, who might be strapped for resources.