The four papers in this dissertation examine the relationship between demographic context and mass and elite political behaviors. The first paper leverages a demographic shock---the movement of massive numbers of African Americans from the American south to California during the ``Second Great Migration'' in the early 20th century---to assess the impact of proximity to demographic change on voting for a racial ballot proposition in 1964. The second paper argues that racial threat can also operate prospectively before demographic shifts occur, what I call ``potential outgroup entry.'' To study this, I examine how a vote for a bond funding the expansion of the BART train in the Bay Area in 1962 was partially shaped by the fear of the potential outgroup entry of a sizable number of black riders from the East Bay into San Francisco. In the third paper I apply theories of demographic change and racial threat to contemporary voting by looking at how both symbolic attitudes and contexts were correlated with vote-switching toward and away from Donald Trump in 2016. Finally, in the fourth paper, I examine the role that context plays in shaping elite behavior. More specifically, I examine how both stable and changing demographics in a state shape electoral incentives and thus the content of campaign appeals by U.S. Senatorial candidates in 2010, 2012, and 2014.