The chart that all the political junkies are sharing today is about the politics of cities. It plots public opinion in 51 large cities on a left-right axis, relative to (what I gather is) the typical American voter. The Economist produced the chart, using a study written by Chris Warshaw of MIT and Chris Tausanovitch from UCLA and published in the American Political Science Review. Here's what it looks like:

Politics of cities, via the Economist

The results aren’t all that surprising. The residents of San Francisco are the most liberal, followed in succession by people living in Washington, D.C., Seattle, Oakland, and Boston. But the real takeaway, as Adrianna McIntyre points out at Vox, is that the vast majority of the 51 cities are on the left end of the spectrum. Less than a dozen skew conservative. They are mostly cites in the South and interior West, such as Colorado Springs and Virginia Beach, known for large populations of religious conservatives.

Assuming that I've read the data correctly and that it holds up to scrutiny, the chart is interesting for its own sake. But it’s also a reminder of a fundamental problem with our democracy, one that’s baked into the constitutional order. I’m talking, of course, about the United States Senate, where the apportionment of two seats for each state can give rural states disproportionate power—power that comes at the expense of urban states, the ones with lots of the left-leaning cities.

This is known as the "small state problem." And while it works out in different ways at different times, most experts I know accept that it's real—and that, these days, it puts liberalism at a political disadvantage.

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