A legislator or candidate by himself, or through others, shall not intentionally undertake, execute, hold, or enjoy, in whole or in part, any contract, agreement, sale, or purchase of the value of one hundred dollars ($100) or more per transaction, made, entered into, awarded, or granted by any state agency, except:
(1) Contracts, agreements, sales, or purchases between a state agency and a business in which the legislator and his spouse, collectively, own or control an interest of five percent (5%) or less;
(2) Contracts, agreements, sales, or purchases made or let after public notice and competitive bidding;
(3) Contracts, agreements, sales, or purchases which are available on similar terms to members of the legislator's business, occupation, or profession; or (4) Contracts or agreements entered into prior to the time the legislator became a candidate. Violation of this section is a Class D felony, and the court upon conviction may void the contract, agreement, sale, or purchase violating this provision.