Nate Silver: Why Are There No Black Senators?

When the House of Representatives convenes tomorrow, it will contain 39 African-American members, not including non-voting delegates in places like the Virgin Islands and the District of Columbia. This number, representing about 9 percent of the Congress, falls somewhat short of the fraction of African-Americans in the population as a whole -- a truly representative House would have about 55 black members -- but perhaps not dramatically so. The situation at first glance would appear to be much better than it was prior to 1990, when there were generally only about 20 black members in the House at any given time.

The districts these 39 Congressmen serve, however, are not very representative at all. All 39 contain a higher percentage of African-Americans than the population as a whole, ranging from Keith Ellison's district in Minneapolis, which is just barely more black than the national average, to Jesse Jackson Jr.'s on the South Side of Chicago, which is 68 percent African-American. About 64 percent of the members -- 25 of 39 -- come from districts that contain an outright black majority. The districts are also much more Democratic than the country as a whole, with an average PVI of D +25; only Sanford Bishop's district in Georgia, which has a PVI of D+2, is anywhere close to the national average.

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