The anti-Chinese sentiment was not confined to fringe political movements competing for local offices. This is the 1888 presidential ticket of the Democratic Party of Los Angeles. Its carries powerful slogans echoing the sentiments and appeals of the Workingmans’ Party: “Exclusion of Chinese” and “Protection of Free Labor.”
“Free labor” is again juxtaposed with Chinese labor which is “slave labor.” In this formulation, Chinese labor is no different from slave labor. The notion of an inevitable and expanding competition between white labor and the slave labor of African Americans was the fundamental appeal of the national Republican Party in the years before the Civil War. 
Over 90 percent of Chinese arrivals in California were men; there were few women. In the years after the Civil War, the Union Pacific Railroad imported 10,000 male laborers through San Francisco contracting companies to build the railroad. American shipping companies were actively involved in the trade. Efforts were made as early as the 1850s to make work contracts struck in China enforceable in California.
Estimates of Chinese arrivals in these early years are inconsistent, but the numbers converge by 1872, with between 76,000 and 84,000 recoded as landing over the next five years, almost all into San Francisco. [E. Sandmeyer, The Anti-Chinese Movement in California (Urbana, University of Illinois, 1939):12] This spike in arrivals coincided almost perfectly with the depth of the depression. Increasing numbers of cheap laborers combined with an increasingly adaptable and skilled resident Chinese workforce created new competition with white labor in a job-scarce depression.

The fact the Democrats were willing to run the anti-Chinese slogans, and that the notion of Chinese slave labor resonated so deeply with major themes of the Republican Party, increased the pressure on the major parties to act. The end result was the 1882 Chinese Exclusion Act which remained in place until 1943 when China became an American ally in the war against Japan.