GENERAL LOCAL ELECTIONS INFORMATION
Local spring elections (general election the first Tuesday in April) are non-partisan. Candidates don't run as a member of a political party—Republican, Democrat, Green, etc.—but instead run without those political party affiliations. This means when there are more than two people run for a seat, regardless of the party they belong to, they will have a primary on the 3rd Tuesday in February.
Most local offices for county board, villages, cities and towns are two year terms. Some offices such as the County Executive or Mayor may be 4 year terms. School board terms are three years. Some bodies have staggered terms, such as 2 or 3 Madison School Board members run each year. Others have all of the elected officials face election at the same time. For example, all 37 Dane County Board Supervisors (elected in even years) and all 20 Madison City Council (elected in odd years) members run every two years. Some candidates run in specific districts that are smaller sections of the geography of the entire area the elected body represents, like Dane County Board and Madison City Council. Others run for for s specific seat, but are elected by the entire geographic area, such as the Madison School Board. Some districts may have more than one representative, for example, in Fitchburg there are two city council seats in each district.
Most of the websites that list their elected officials list not only their contacts, but when the terms expire. See here for county board, school boards, cities, towns and villages. With the media cutbacks in recent years, there often isn't much attention given to when people need to run for office. While some websites provide a lot of information about how to run, others simply post their formal notice. Others do nothing.
For spring elections, candidates start circulating nomination papers December 1st and nomination papers and the other paperwork necessary to get on the ballot are due the first Tuesday in January. Incumbents are also given a deadline for when they have to file a notification of non-candidacy if they are not running again and if they don't meet the deadline, candidate paperwork deadlines will be extended.
These are the constitutional offices and the terms of their office.
Sheriff - 4 year term
County Clerk - four year term
County Treasurer - four year term
Register of Deeds - four year term
Clerk of Court - two year term
District Attorney - four year term
These elections are in the fall and people run under a specific party. Information for these offices for Dane County is here. The Primary is the second Tuesday in August and the Election is the second Tuesday in November.
If the sheriff, register of deeds, judge or district attorney leaves before their term is over, the governor appoints the replacement. Dane County no longer has an elected coroner, we have a medical examiner.