Congressional district allocation is not proportional representaton
Nebraska is one of two states allocating its electoral votes by congressional district, not statewide. In an article on the still disputed status of the electoral vote corresponding to NE-2, the New York Times gets it wrong:
Unlike every other state but Maine, Nebraska allocates its five electoral votes proportionally. The winner does not take all. So even though Mr. McCain won the statewide popular vote, it looks as if Mr. Obama was able to carve out a piece of the state, the Second Congressional District, for himself. The district includes most of metropolitan Omaha. [emphasis mine]
Colorado is the most recent state - if not the only - to have considered and defeated allocating its electors in proportion to candidates’ vote shares. Maine and Nebraska do not. In those states, the statewide winner gets the two electors corresponding to the states’ Senators, and the elector corresponding to each congressional district goes to the candidate winning that district.
The conflation of PR and single-member districts is relatively unique to American political culture. I believe it is a legacy of our founding.
When the Framers met in 1787, the debate over legislative representation was framed in terms of apportionment. Would all states receive equal numbers of seats (New Jersey Plan), or would apportionment be proportional to states’ populations (Virginia Plan)? The Connecticut Compromise, of course, gave us both: equal delegations in the Senate and “proportional” delegations in the House. A search of the Federalist Papers for the string “proportional representation” returns references, but all mean proportional apportionment by population of the seats each state will elect - not proportional allocation by vote share of a state’s seats to parties. To this day, the Wikipedia article for New Jersey Plan cited above still calls proportional apportionment “proportional representation.”
This is not surprising. Proportional representation as framed today, of parties by vote shares, did not exist until two generations later, when Thomas Hare articulated and J.S. Mill popularized the concept. (See also a later essay by Henry Droop.)
Had PR existed, of course, the Framers likely would have opted for it. PR is consistent with the views in Federalist No. 10 on “controlling [faction's] effects.” By multiplying the factions represented, one reduces the likelihood that a tyrannical majority will emerge.
A fundamentally majoritarian system in which seats are allocated to states in proportion to their populations can deliver proportionality of seats to votes more or less by accident, but that is not a proportional representation system.