House seats held by Republicans generally have significantly lower foreign-born populations than those held by Democrats, a likely indication of why the two parties are so far apart on immigration — especially in the lower chamber.

Why this matters: The clock is ticking on protections for immigrants brought to the U.S. as children, and Congress isn't close to a solution. It's obviously members' job to reflect the interests of their constituents. When the majority of a district's voters don't have any skin in the game, meeting in the middle can be tough.