5 U.S. Code § 1503
5 U.S. Code § 1503 is about Nonpartisan candidacies permitted. It is under Part 2 (Civil Service Functions And Responsibilities) Chapter 15 (Political Activity Of Certain State And Local Employees) of Title 5 (Government Organizations and Employees) of the Code.
Section 1502(a)(3) of this title does not prohibit any State or local officer or employee from being a candidate in any election if none of the candidates is to be nominated or elected at such election as representing a party any of whose candidates for Presidential elector received votes in the last preceding election at which Presidential electors were selected.