Cillizza on the Ideological Middle

Chris Cillizza writes an interesting column for the Washington Post on the decreasing number of moderates in the House and Senate.  ("The ideological middle in Congress is dead.  So, who killed it?" 4/15).

One very interesting point, gerrymandering gets blamed for the increasing partisanship in the House, but it shouldn't affect the Senate as those are statewide races.  Hadn't thought of that.