Ok, I'll put it very simply for you, since you're having comprehension issues:
Nebraska allocates Electoral College votes by congressional district. 1 for NE-1, another for NE-2, a third for NE-3, and the two remaining to whoever wins the state overall. This way more constituents are represented, as if you live in a predominantly R or D area your EC votes go to the R or D instead of getting washed out by whoever wins the state. Republicans are now trying to change this to winner-take-all because Ds have started winning one district consistently, splitting NE's total votes 4 and 1. Instead of trying to win voters, they want to change the Electoral College process so that those voters' voices are silenced.
How is that consistent with supposed Republican/conservative values of federalism and self-determination?