Newly released documents from the Republican administration of President Richard Nixon in the United States reveal a racial strategy was considered for Mr Nixon's 1972 re-election campaign.
CNN reports the aim appears to have been to sow controversy among the rival Democrats by anonymously promoting the idea of a black presidential or vice-presidential candidate for the Democratic Party.
One document entitled Dividing the Democrats proposed the distribution of bumper stickers in urban ghettos calling for "black presidential and especially vice-presidential candidates."
The idea was that having a black candidate on the ticket might make Mr Nixon's opponents unelectable.
The notice is unsigned but archivists believe it was written by Nixon aide Pat Buchanan, who later ran for president himself. There is nothing to indicate that Mr Nixon wrote or approved any of the documents.