List of Lieutenant Governors of Wisconsin

The lieutenant governor is the first person in the order of succession of Wisconsin's executive branch, thus serving as governor in the event of the death, resignation, removal, impeachment, absence from the state, or incapacity due to illness of the Governor of Wisconsin.

Until 1979, the Wisconsin Constitution merely stated that in any of these events, "the powers and duties of the office [of Governor of Wisconsin] shall devolve upon the lieutenant governor". Lieutenant governors who served as governor during this period are referred to as "acting governors". In 1979, the constitution was amended to make this more specific: in the event of the governor's death, resignation, or removal from office, the lieutenant governor becomes governor; in the event of the governor's impeachment, absence, or incapacity, the lieutenant governor becomes acting governor until the governor is again able to serve.

Under the original terms of the state constitution, the lieutenant governor was elected for a two-year term on a separate ticket from the governor; because of this, the Governor and Lieutenant Governor of Wisconsin have not always been of the same party. After a 1967 amendment, however, the two have been nominated, and voted upon, as a single ticket. Another 1967 amendment increased the terms of both the governor and lieutenant governor to four years. There is no limit to the number of terms a lieutenant governor may hold.

The original constitution made no provision for a vacancy in the office of the lieutenant governor; in the event of the lieutenant governor's death or resignation, the lieutenant governorship usually remained vacant until the end of the term. In 1938, following the resignation of lieutenant governor Henry Gunderson, Governor Philip La Follette appointed Herman Ekern lieutenant governor to fill the vacancy. This appointment was challenged in court, and ruled valid in the case State ex rel. Martin v. Ekern. In 1979 the constitution was amended to explicitly allow this: in the event of a vacancy in the office of the lieutenant governor, the governor nominates a candidate who becomes lieutenant governor for the remainder of the term upon his approval by the Wisconsin Assembly and Wisconsin State Senate.

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