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3 U.S. Code § 2 - Failure to make choice on prescribed day

Whenever any State has held an election for the purpose of choosing electors, and has failed to make a choice on the day prescribed by law, the electors may be appointed on a subsequent day in such a manner as the legislature of such State may direct.

(June 25, 1948, ch. 644, 62 Stat. 672.)