The early 2028 Republican vice-presidential market remains tightly bunched because no presumptive presidential nominee has emerged more than two years before primaries, leaving traders pricing in a fragmented field of Trump-aligned figures with cabinet posts, media profiles, or family ties. Marco Rubio’s State Department role and recent foreign-policy visibility, Vivek Ramaswamy’s outsider messaging, Tucker Carlson’s audience reach, and Ivanka Trump’s name recognition each command roughly one-fifth of the probability, reflecting competing visions of the ticket’s ideal balance. J.D. Vance’s lower share as sitting vice president underscores that incumbency alone does not confer VP certainty. Developments such as 2026 midterm results, explicit endorsements from the current administration, or shifts in primary polling could quickly consolidate support behind one or two names while diminishing others.