Technically, the POD says African American, so...
the Great Trek hits a snag earlier and more comprehensively (say the Xhosa are better armed or more able to hurt the Trekkers). Boer discontent with British rule simmers and in the course of the 1830s and 1840s, many wealthy Boer families choose to move to the United states. They settle mostly in Indiana and Missouri, later in Kansas and Arkansas. Boer communities take up collections to allow others to follow. Nonetheless, these communities always stay small.
In 1888, Indiana sends Republican John Cornelius Verwoerd to the House of Representatives for the first time. Verwoerd is a lawyer, third son of a Boer settler who owns a timber company and mining and shipping interests. He has already spent a term in the state legislature and lost a campaign to be made governor. His further political career is meteoric. In 1896, while serving as the Indiana representative on the Republican National Committee, he is offered the nomination as vice president to William McKinley and accepts. After a largely uneventful tenure during which Verwoerd develops a close bond with President McKinley, he becomes President following McKinley's assassination.
I know, I know....