Must Ohio delegates vote for only 1 Presidential candidate?

About half of the states have laws designed as a guarantee to back up the pledge to vote a certain way that every elector makes. I know that Ohio is one of those states, but I don't know what their presidential election law(s) say(s).

Generally speaking, each state has a right to choose the method for deciding how each elector is chosen. I don't know if those rules are laws or traditions, but in either case the state can change them (it just takes longer to change a law than to change a tradition).

Of the 52 elections in which Ohio has participated to date since becoming a state, there has been only one in which Ohio has split its vote: In 1892, Ohio cast 22 votes for the Republican ticket, Harrison/Reid, and 1 vote for the Democratic ticket, Cleveland/Stevenson.