The New Republic's Franlin Foer lays out the case:
These are boom times for provincial autocrats. In many chunks of the country, state and local politics were once a competitive affair; there was an opposing political party ready to pounce on its foe’s malfeasance. That sort of robust rivalry, however, hardly exists in an era in which blue and red states have become darker shades of themselves. Thirty-seven states now have unified governments, the most since the early ’50s. And in many of these places, there’s not even a remote chance that the ruling party will be deposed in the foreseeable future. The rise of one-party government has been accompanied by the evisceration of the local press and the near-extinction of metro-desk muckrakers (14,000 newsroom jobs have vanished in the last six years), crippling the other force most likely to call attention to official misdeeds.
The end of local media hasn’t just removed a watchdog; it has helped to complete a cultural reversal. Once upon a time, Jefferson and Tocqueville could wax lyrical about local government, which they viewed as perfectly in sync with the interests of its yeoman citizenry. Whether this arcadia ever truly existed is debatable. But it certainly hasn’t persisted into the age of mass media. Nowadays, most Americans care much more passionately about national politics than they do about the governments closer to their homes. They may harbor somewhat warmer feelings toward states and localities, but those sentiments are grounded in apathy. Most Americans can name their president. But according to a survey conducted by Georgetown University’s Dan Hopkins, only 35 percent can identify their mayor. The nostrum that local government is actually closer to the people is now just a hollow piece of antique rhetoric.
With so many instances of unobstructed one-party rule, conditions are ripe for what the political scientist Jessica Trounstine calls “political monopoly”—officials and organizations who have so effectively defeated any potential predators that they can lazily begin to gorge. She writes: “When politicians cease to worry about reelection, they become free to pursue government policy that does not reflect constituent preferences. They acquire the ability to enrich themselves and their supporters or pursue policies that would otherwise lead to their electoral defeat.”
I wonder, though, whether this will lead to more vigorous intra-party competition. Here in Chicago we've had one-party rule for decades, but usually with an opposing state government. We're now starting to see real competition in the primary races that we didn't have under the Daleys.
Of course, we could become China.