California was still counting, and President Donald Trump saw a rare setback as results came in from primary elections across the country.

With so many key races expected to be tight, officials are warning it could takes days to know the outcome of California's primary election. Here are some important things to watch as the results roll in.

While voting has ended in California's primary election, election officials in Sacramento County say the work of counting ballots is far from over. Officials say the next update of election results