The Constitution established the following guidelines for federal elections:
Although the Constitution established the foundations for federal elections, specific laws and rules that shape the actual voting process and determine who is eligible to vote are created by the individual states. However, the federal government can challenge and sometimes overrule state election policies that it considers unconstitutional.
The following links and video provide more detailed explanations of federal elections.
The Constitution created the formal structure of the federal government, and it established the original rules governing national elections. Since its ratification, however, it has been amended numerous times in ways that fundamentally affect national elections. Perhaps the most significant amendments were those that extended the right to vote to populations such as women and people aged 18-21. Other amendments altered the mechanisms by which senators are elected and limited the president to two terms.