Google announced that, once the polls close on November 3rd, it will temporarily ban advertising that references the 2020 election, the candidates, or the outcome of the election.  Google said that it is taking this action in light of the "possibility of delayed election results" and "to limit the potential for ads to increase confusion post-election." 

Google said that it is taking this action in accordance with its Sensitive Events policy, which prohibits, "Ads that potentially profit from or exploit a sensitive event with significant social, cultural, or political impact, such as civil emergencies, natural disasters, public health emergencies, terrorism and related activities, conflict, or mass acts of violence." 

Facebook previously announced that it is taking similar action.