Inside Wisconsin: Why Milwaukee doesn't need to be Madison, and Madison doesn't need to be Austin, by Tom Still. (Wisconsin State Journal, 11/2/2013)
The quibble (sense 2 of the noun): Austin has always been a much larger city than Madison.
Actually, there was some see-sawing of the lead from 1850 to 1940.
A similar pattern is occurring with statewide population growth.