However, I find this statistic to be very misleading. Yes, Chicago's population is 2,836,658, but that doesn't include all the surrounding suburbs and nearby cities that constitute a concentrated base of fans. A more accurate stat is the population of metropolitan statistical areas and wiki has a table for that as well.
Now we can easily see which largest metro areas don't have MLB teams and how they rank against the smallest MLB markets. I don't know why Google lists Riverside as its own city. It's really part of the Los Angeles metro area in my opinion. Riverside residents can easily make the trip to see a Dodgers or even an Angels game.
The largest metropolitan area without a baseball team is Portland. Poor Portland. They're not even close to traveling to San Fran, Oakland, or Seattle for a game. The whole mix of metro areas from 22-30 is interesting. I'll list them again here in a more concise list:
22. Pittsburgh - YES
23. Portland - NO
24. Cincinnati - YES
25. Sacramento - NO
26. Cleveland - YES
27. Orlando - NO
28. San Antonio - NO
29. Kansas City - YES
30. Las Vegas - NO
In theory, Portland, Sacramento, Orlando, San Antonio, or Las Vegas can have a Major League Baseball franchise because there's other markets of similar size that do have a MLB team.
And then all the way down at 39 is Milwaukee. There are 13, count 'em 13 metro areas that are larger than the metro-Milwaukee area that don't have MLB teams. How does Milwaukee do it?
Milwaukee should be part of the Chicago area. Milwaukee is a suburb of Chicago anyways. Why not include it with Chicago? That would bring chicago's population up to 11 million, and we'd have three teams. Chicago rules.
Does Kansas City really need a team?
I always thought it was dumb to move the Expos to DC. But I guess they have the population to support it.