Congressional stagnation in the United States

Congressional stagnation is an American political theory that attempts to explain the high rate of incumbency re-election to the United States House of Representatives. In recent years this rate has been well over 90 per cent, with rarely more than 5-10 incumbents losing their House seats every election cycle. The theory has existed since the 1970s, when political commentators were beginning to notice the trend, with political science author and professor David Mayhew first writing about the "vanishing marginals" theory in 1974.

The term "congressional stagnation" originates from the theory that Congress has become stagnant through the continuous re-election of the majority of incumbents, preserving the status quo.

In the 2000 Congressional Elections, out of the 435 Congressional districts in which there were elections, 359 were listed as "safe" by Congressional Quarterly. In all of these 359, there was no uncertainty as to who would win. The results a week later confirmed that very few House races were competitive. The 2000 House election resulted in a net change of only four seats (+1 for the Democrats, −2 for the Republicans and the electing of an additional independent). In total, 98% of all incumbents were re-elected.

Congressional elections are stagnant, and because of the high invincibility of House incumbents, very few districts are truly competitive, with elections shifting very few seats from one party to another. One of the most important reasons as to why incumbents are nearly unbeatable is because they normally have much better financed campaigns than their opponents. Other potential theories include the aggressive redrawing of congressional boundaries known as gerrymandering, from a more historical perspective the loss of party alignment, or the simple fact of being an incumbent.

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