Ohio Rev. Code Ann. § 3513.301
(A) Notwithstanding section 3513.30 of the Revised Code, if only one person has filed a valid declaration of candidacy for nomination as the candidate of a political party for the office of representative to congress and that person withdraws as a candidate or dies at any time before the primary election, a special election shall be held under division (B) of this section to nominate the following:
(2) The candidate for congress of any other major political party under either of the following circumstances: