Delaware shares its vote with Wyoming because Rhode Island, which used to share the electoral vote with Delaware, became emancipated electorally by a state constitutional convention in the 1960s.
The only other states that share their electoral votes are South Dakota and Montana. This arrangement will last until 2016, at which time both states are free to enter into an electoral arrangement with another state. Idaho used to share with Wyoming until Wyoming linked up with Delaware.
Massachusetts, Texas, Tennessee and New Mexico are barred from sharing electoral votes with other states because of laws enacted by their state legislatures.
Also by virtue of double secret Amendment 22(a) to the U.S. Constitution votes in certain precincts in Sourth FLorida may be traded with precincts in New York so long as it can be demonstrated that 30% of the people in the Florida precincts coe from the same ten zip codes in New York where their votes may be counted.
