25 Pa. Stat. § 3031.19
If in any case the number of candidates nominated or seeking nomination for any office, or if a method of election for any candidate or office which is prescribed by law, renders the use of an electronic voting system impracticable, or if, for any other reason the use of an electronic voting system is not possible or practicable at a particular election, the county board of elections may arrange to have the voting at any such election and for any such offices conducted by paper ballots. In such cases, the ballots shall be printed for any such election or office and the election shall be conducted by the election officers herein provided for, and the ballots counted and the return thereof made in the manner required by law for such offices insofar as paper ballots are used.
25 P.S.§ 3031.19