Why are vacancies getting longer? One reason is that it simply takes more time to conduct a special election these days. In 2009, Congress passed the Military and Overseas Voter Empowerment Act, which requires states to send requested absentee ballots to overseas voters at least 45 days before any federal election. Add in time to print the ballots and double the result because most special elections include both a primary phase and a general phase, so you’re looking at a special-election period of at least 100 days. But a simple election-law change doesn’t explain the whole increase. Take a look at the table below, which lists the 10 House seats that have sat vacant the longest since 1997. Nine of them have something in common: Not only did the vacancies take place in the past 10 years, but the representatives who vacated the seats did not belong to the same party as the governors of their states. The latter is noteworthy because governors are almost always the ones who choose the dates for House special elections.