Special Elections

Whenever there is a vacancy in the House, it takes a special election to fill it. This week, there will be a special election to fill the seat of Chris Lee, an upstate New York Republican who quit because about embarrassing revelations about his personal life. At MSNBC.com, Tom Curry explains that political observers will be watching closely:

Special elections resulting in party switches do have predictive value, according to newly published research by Tom Brunell, professor of political science at the University of Texas at Dallas and graduate student David Smith.

Brunell and Smith studied every House special election between 1900 and 2008.

They found that “when a party picks up more seats in a set of special elections than the other party gains, the more successful party can usually count on picking up seats in the next general election.” Their research was published in the latest issue of Legislative Studies Quarterly. [See MPSA paper here.]

They found that when the Republicans have a net gain in special elections, they win seats in the following general election two-thirds of the time. “For the Democrats, the relationship is even stronger: when they take seats away from the Republicans in the special elections, Democrats follow up with a seat gain in the general election 82.35 percent of the time.”

For every net seat gain by a party in a special election, the party can expect to pick up on average more than six seats in the following general election.

But as they note, most special elections don’t indicate any trend at all because in most cases Democrats keep what had been safe Democratic districts and Republicans win what had been safe GOP districts.

…

University of Oklahoma political scientist Keith Gaddie, who had studied special elections, said, “When they occur, they behave just like regular open seat elections,” that is, House races on the regular November ballot where an incumbent has decided to not run again and new candidates are vying for the seat.

“In highly competitive districts, a change in control that happens in a special election would probably have happened under the same set of circumstances in November,” Gaddie said. “Open seats should be more vulnerable to national tides because of the absence of incumbents — and they are.”