for years every state in the union awarded its electoral votes in a presidential race with a winner-take-all system, except two: maine and nebraska used a proportionate system where the winner of each congressional district gets one electoral vote for that district, plus two additional electoral votes for the candidate that gets the most vote in the state. now with the GOP in pennsylvania considering a switch to a proportionate system, the nebraska GOP is pushing to switch that state to a winner-take-all system.
if both changes to through it would not be a wash, however. NE has only 5 EVs whereas PA has 20. PA is a purple state (with some congressional districts that are solidly red, some that are solidly blue and several others that swing) whereas NE is pretty solidly red in every district. in 2008, there was some early speculation that obama might be able to peel off one of NE's EVs, but that didn't actually happen and the state gave all of its EVs to mccain. if obama couldn't pull it off in 2008, it's even more unlikely he will in 2012. i expect that nebraska will be solidly red no matter what system it uses.
if both changes to through it would not be a wash, however. NE has only 5 EVs whereas PA has 20. PA is a purple state (with some congressional districts that are solidly red, some that are solidly blue and several others that swing) whereas NE is pretty solidly red in every district. in 2008, there was some early speculation that obama might be able to peel off one of NE's EVs, but that didn't actually happen and the state gave all of its EVs to mccain. if obama couldn't pull it off in 2008, it's even more unlikely he will in 2012. i expect that nebraska will be solidly red no matter what system it uses.