Ohio Rev. Code § 3513.11
In the year 1952 and in each second year thereafter, each major political party in the state may hold a state convention. If a major political party holds a state convention, it shall comply with the requirements of this section. A state convention of a major political party shall be composed of delegates who are its candidates for election to state offices, except judicial offices; its candidates for election to the office of member of the senate of the United States, member of the house of representatives of the United States, and member of the general assembly of Ohio; the members of its state central and executive committees, and the chairman of its county central and executive committees; and five hundred delegates to be apportioned by the state central committee of the respective parties among the several counties of the state in proportion to its party's vote for governor cast in the several counties at the most recent general election; provided that in any even-numbered year in which no election is to be held to elect successors to incumbents of any of the offices mentioned in this section, except judicial offices, each such incumbent shall also be a delegate to the state convention of his political party. The delegates to such convention apportioned to each county by the state central committee of the respective parties shall be selected by the county executive committees of the respective parties.
At each convention of a major political party, the state platform of such party for such year shall be formulated.
The state central committee of each political party shall fix the time and place for holding the convention of its party, except that the state convention shall be held no later than forty days prior to the general election.
At the state convention of each major political party held in 1952, and in each fourth year thereafter, persons shall be nominated as candidates for election as presidential electors to be voted for at the succeeding general election. Within five days after the holding of each such convention, the chairman and secretary thereof shall certify in writing to the secretary of state the names of all persons nominated at such convention as candidates for election as presidential electors.
R.C. §3513.11