Senate races in Arizona, Nevada still not called; Democrats hold slim leads

Three days after Election Day on Nov. 5, the U.S. Senate races in the western states of Arizona and Nevada remain undecided.

Democratic candidates in both races have maintained a slight lead, offering hope for Democratic leader Chuck Schumer that his incoming minority might not shrink further. Republicans have flipped four senate seats so far and are set to start next year in the majority. 

As of Friday morning, incumbent Sen. Jacky Rosen, D-Nev., leads her Republican challenger Ret.