Ind. Code § 3-10-5-5

Sec. 5. Each county shall elect at least one (1) delegate to the convention prescribed by section 1 of this chapter. In addition, each county having a population greater than twenty thousand (20,000) shall elect one (1) additional delegate for each additional twenty thousand (20,000) persons in the county, or major fraction thereof. The governor shall determine the number of delegates to which each county is entitled under this section and shall include the number in the governor's proclamation.