Swing states are states in American politics that could reasonably be won by either the Democratic or Republican candidate in a statewide election, most often referring to presidential elections. They are also known as battleground states, toss-up states, or purple states. The key characteristics of swing states are that they have small vote margins and that different political parties win over time.

Presidential campaigns and pundits focus on swing states because they could potentially be won by either candidate, and their outcomes can be decisive in winning the presidency. In contrast, safe states are those that opinion polls leading up to the election identify as being highly likely won by a particular partys candidate, and they are not prioritized in terms of allocating time and resources during the election campaign.

Swing states have generally changed over time, and determining states likely to be swing states in future elections requires estimation and projection based on previous election results, opinion polling, political trends, recent developments since the previous election, and any strengths or weaknesses of the particular candidate involved. Some examples of swing states in recent elections include Arizona, Georgia, Michigan, Pennsylvania, and Wisconsin.

In conclusion, swing states are states in American politics that could reasonably be won by either the Democratic or Republican candidate in a statewide election, most often referring to presidential elections. They have small vote margins and different political parties win over time. Presidential campaigns and pundits focus on swing states because they could potentially be won by either candidate, and their outcomes can be decisive in winning the presidency.