Final answer:
There is no exact number provided for KKK membership in Indianapolis during the 1920s, but the second Ku Klux Klan reportedly had six million members by 1924. It was prominent in the West, South, and Midwest, but declined later in the 1920s due to scandals and public condemnation.
Step-by-step explanation:
The exact number of Ku Klux Klan members present in Indianapolis in the 1920s is not specified in the given materials, but it is stated that this second incarnation of the Klan, established shortly after the release of the film Birth of a Nation, gained substantial acceptance and boasted up to six million members by 1924. This second Ku Klux Klan was particularly populous in the West, South, and Midwest, so it's likely there was a significant presence in Indianapolis. However, the organization's popularity waned in the late 1920s due to public scandals and increasing public condemnation, such as from influential figures and citizens' groups, culminating in a significant loss of members during the Great Depression.
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