Presidential Elections
The United States Constitution stipulates that a presidential election is to be held once every fourth year. The process of electing a president and vice-president, however, begins long before election day.

The nominating process within the political parties officially begins with the first state primaries and caucuses, which usually occur in the month of February of the election year. These primaries and caucuses choose slates of delegates (usually pledged to support particular candidates) to represent the state at the national party conventions.

At the national party conventions, traditionally held in the summer, the delegates from the states cast votes to select the party's candidate for president.

On election day -- the first Tuesday following the first Monday in November of an election year -- every citizen of legal age who has taken the steps necessary in his or her state to meet the voting requirements (such as registering to vote) has an opportunity to vote. However, the president is not formally chosen by direct popular vote. The constitution calls for a process of indirect popular election known as the electoral college.

The Electoral College
The political parties (or independent candidates) in each state submit to the chief election official a list of electors pledged to their candidate for president and equal in number to the state's electoral vote. Each state is allocated a number of electors equal to the number of its U.S. senators (always 2) plus the number of its U.S. representatives.

Following election day, on the first Monday after the second Wednesday in December, these electors assemble in their state capitals, cast their ballots, and officially select the next president. As a rule, whichever presidential ticket gets the most popular votes in a state wins all of that state's electors (except in Maine and Nebraska).

The president-elect and vice president-elect take the oath of office and are inaugurated on January 20th.

Congressional Elections
The Congress is divided into two chambers, the Senate and the House of Representatives.
The Senate is composed of two members from each state, as provided by the Constitution. Its current membership is 100. Senators are elected to serve six-year terms; every two years one third of the Senate is up for reelection. Before 1913, senators were chosen by their state legislatures, as the Founding Fathers believed that since the senators represented the state, the state legislature should elect them. The 17th amendment to the constitution changed this procedure, mandating that senators be elected directly by the voters of their state.
When the first Congress met in 1789, there were 59 members of the House of Representatives. As the number of states increased and the population grew, the number of representatives increased significantly. A law passed in 1911 fixed the size of the House of Representatives at 435 members. Members of the House are up for reelection every two years. The number of representatives in each state depends upon its population as reported in the nation's most recent census. Each state is divided into a corresponding number of congressional districts. There is a representative for every congressional district, elected by the voters residing in that district.

State and Local Government
Like the national government, state governments have three branches: executive, legislative, and judicial; these are roughly equivalent in function and scope to their national counterparts. The chief executive of a state is the governor, elected by popular vote, typically for a four-year term (although in a few states the term is two years). Except for Nebraska, which has a single legislative body, all states have a bicameral legislature, with the upper house usually called the Senate and the lower house called the House of Representatives, the House of Delegates, or the General Assembly.

Types of city governments vary widely across the nation. However, almost all have some kind of central council, elected by the voters, and an executive officer, assisted by various department heads, to manage the city's affairs.