More than 500 monitors and observers will watch polling sites in 28 states, looking for voting rights violations such as discrimination against voters because of their race or language.
Republicans are feeling the best they have this cycle about their chances of holding their majority, but even doing that requires several states to break their way on election night.
Hillary Clinton retains a broad, consistent and shallow lead over Donald Trump in battleground states. If her Blue Wall of states leaning her direction holds, she wins. If not, anything can happen.
The GOP is still favored to control the House. Donald Trump hasn't been the boon Democrats need. But some longtime GOP incumbents could go down, as Democrats stand to pick up a dozen or more seats.
In the last hours of campaigning, analysis of what to make of these final days of this long election season and what voters should be thinking about going forward.
U.S. electoral demographics have drastically changed in the past few decades. Brookings Institution demographer William Frey provides analysis, along with NPR's Asma Khalid and Domenico Montanaro.