10 ILCS 5/17-25

The days upon which the general elections for members of the House of Representatives of this State shall hereafter be held shall be holidays, and shall for all purposes whatever as regards the presenting for payment or acceptance and of protesting and giving notice of the dishonor of bills of exchange, bank checks and promissory notes and as regards days of grace upon commercial paper, be treated and considered as is the first day of the week, commonly called Sunday; provided, that no other election day shall be treated and considered as a holiday.