What You Need to Know About the U.S. Midterm Elections

Every two years, voters in the U.S. elect a new House of Representatives and one-third of the 100-seat Senate. This Election Day, today, is widely seen as a referendum on someone not on any ballot: President Donald Trump. The midterm election -- so named because it comes at the middle of the president’s term -- will determine whether Trump’s Republican Party retains control in the House and Senate or whether Democrats will gain control of one or both and begin to spell all kinds of problems for Trump.

It depends on how quickly votes are counted and how close the races are. Many contested House seats are in eastern states like Florida, North Carolina, Pennsylvania and Virginia; by 8 p.m. Eastern Standard Time, voting in those states and many others will be done. It’s possible that control of the next House could be clear by 11 p.m. EST, when polls close in populous California. If not, a long wait is possible: There are more than half a dozen competitive House races in California, where there’s a prolonged ballot-counting process and many voters cast ballots by mail. Some key Senate races are in western states, so results may not be known until Wednesday; close races could require recounts that could add many days to the waiting time.