Ohio,  A Bellwether State

Q. What the heck is a bellwether state? 
 
 
A. A bellwether state is a state that frequently favors the winner in national elections.  Elections observers watch these states closely as indicators of the final results of an election.  Ohio is considered a bellwether state for its long record of voting with the winner in presidential elections.


Old Reliable (aka The Oxford English Dictionary, 2nd edition) gives the following definitions and uses of bellwether:

definition 1.
The leading sheep of a flock, on whose neck a bell is hung.
early usage:
(1867)  II. 254 Men are for the most part like sheep, who always follow the bell-wether.

definition 2.
fig. A chief or leader. (Mostly contemptuous.)
early usage:
(1730) I. 73 The principal bell-weathers of this mutiny. (1794) SOUTHEY Wat Tyler III. i. Wks. II. 50 You bell-wether of the mob. (1848) LOWELL Biglow P. i, 'Taint afollerin' your bell-wethers Will excuse ye in His sight.

Hence... bell-wethering, the fact of leading and being led like sheep and bell-wetherishness, tendency to follow one who takes the lead.