Indiana Code Title 3. Elections § 3-8-3-11

Sec. 11. A delegate or alternate delegate selected from a congressional district to the national convention of a political party shall, on the first ballot at the national convention, support the candidate for President of the United States who received the highest number of votes in the congressional district at the primary election if the person is in fact a candidate at the convention.  A delegate-at-large or alternate delegate-at-large to the national convention is not required to support a specific candidate for President on any ballot at the convention.