Congressional elections | Political participation | US government and civics | Khan Academy

Here's a statistic that might surprise you: 95% of elected officials who seek re-election in the United States get re-elected.

Just look at this graph that shows the rate of re-election for members of the U.S. House of Representatives; it hovers all the way up here. It stands to reason that if you have two candidates for every office, one from each party, it would be about fifty percent of the time the candidates would be re-elected, but it's so much more than that.

In this video on congressional elections, I want to talk about some of the structural aspects—that is, the way things are set up in congressional elections—that leads to this really high number. What are the advantages of being an incumbent? That is, the person who already holds a political office.

So, what kind of advantages does an incumbent have simply for already occupying an office? Well, say maybe there's a Senate race between candidate Green—call her Amy Green—and candidate Rose—maybe he's Ken Rose. Now, what sort of advantages might Amy Green have just because she already holds this Senate seat?

Well, one of her advantages is that she has a staff. She has people whose job it is to answer the phone calls of constituents, make them feel heard; they can do all sorts of things to help her. She also has the advantage of mail. Members of Congress can send out mail for free, whereas candidate Rose over here has to pay for staff and pay for mail. Already, that's a lot of money.

The other thing that candidate Green has going for her is name recognition. She's already been a successful candidate, which shows that she knows how to win an election, and there's a lot of advantage to having name recognition. It's its own kind of advertising. Are you going to vote for someone you've never heard of before, or someone who frequently appears in the media, who could be going to local or state events, school openings? You get a lot of face time simply from occupying a seat, and that's free advertising as well.

The last aspect is money. Because of this incumbency advantage—and this is a little bit of repeating cycle—interest groups, lobbyists, and others are far more likely to give money to the candidate who is already in a position because they know that candidate is likely to win, and therefore, their money is going to get them access to that candidate who will hear out their concerns and perhaps look upon them favorably.

So, compared to all of this, candidate Rose has a really uphill battle. He's got to pay for a lot of things that the incumbent doesn't have to. He doesn't have the name recognition or the automatic media attention, and he's viewed less favorably by the people who might give money. He's a bit of an unknown quantity.

Another advantage that incumbents have is that they get to draw voting districts, at least every ten years in response to the U.S. Census and changes in populations. The districts and states must be redrawn. Politicians do that redrawing, and they tend to use this opportunity to create safe districts for themselves—safe being districts where the voters, who are arranged geographically, will be likely to vote them back into power.

Those in power will also generally use this opportunity to attempt to harm their opponents in a process known as gerrymandering. There are two other major factors that contribute to whether a congress member is re-elected. One of them is, in each state, the form that their primary takes.

Some states, like Iowa, have caucuses where party members gather to vote on who their nominee should be. These are very tightly controlled by the party. There are closed primaries where only the registered members of a party may vote on their party's nominees for election, and then there are open primaries where any registered voter can vote for a party nominee, even if they belong to the opposing party.

So, the form a state's primary takes has a strong effect on how tight the party control is over that process. The last factor affecting congressional elections is whether or not they coincide with a presidential election.

There's much higher voter turnout for presidential elections since there's a great deal of interest in them and money spent on them, and that means that you tend to get a broader sample of the population. More people are likely to vote, so you'll have a better idea of how the American voting public is feeling more generally.

But in midterm elections—which are those elections that don't fall at the same time as a presidential election—voter turnout is lower, and that means that it's going to be the really engaged voters who are often strongly aligned with a party that will come out. Midterm elections also tend to punish the party in power.

So, when the president is highly regarded and doing well, his or her party tends to gain seats. But if the president is doing poorly or has a low public opinion rating, then congressional seats will often go to the opposite party. You can see here this chart of net gain and loss of the president's party, and in most cases, the president will gain a few followers in the first midterm election.

See here George W. Bush 2002; his party gained both House and Senate seats. But often, in the sixth year of a two-term presidency, voters harshly punish the president's party. You can see that in George W. Bush's sixth year; Republicans lost 30 House seats and six Senate seats.

A similar effect happened with Barack Obama in 2014; the Democrats lost 13 House seats and nine Senate seats. So, there's a strong correlation with the president's party and the fates of members of Congress who belong to that party.