Party switching in the United States

In the United States politics, party switching is any change in party affiliation of a partisan public figure, usually one who is currently holding elected office. Use of the term "party switch" can also connote a transfer of held power in an elected governmental body from one party to another.

There are a number of reasons that an elected official, or someone seeking office, might choose to switch parties. One reason is ethical obligation when the person has views that are no longer aligned with those of the current party.

A second reason is to gain powers and influences. The incumbent may be a member of the minority party in a legislature and would like to gain the advantages of being in the majority party, such as the potential to chair a committee. A disaffected incumbent who might not hold a leadership position or feels ignored or mistreated by the majority party might join the minority party with the expectation of holding a leadership position in the minority party and if currently elected, having the complete support of the minority party for re-election, who would certainly want to have more elected officials in their ranks. These people are usually looked down upon by the media and in popular culture.

Another reason is simply to get elected. This may be the primary reason when the opposing party's base in a constituency is reaching a size that threatens the safe reelection of the incumbent or the elected official fears being primaried.

The shifting of allegiance between political parties was much more common during the 19th century than in recent times. Many parties formed and fell apart rapidly.

A massive party switch occurred in the 19th century and 1810s when many members of the United States Federalist Party joined the United States Democratic-Republican Party. When this party fell apart in the 1820s, its members all switched to various political parties, including the United States Whig Party, as well as the Democratic, National Republican, Anti-Jackson and Anti-Mason Parties. The Republican Party was also formed by a massive party switch in 1854 when northern members of the Whig, American and Free Soil parties, along with many northern Democrats, formed the Republican Party, and many Southern Whigs became Democrats.

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