Five reasons why Republicans lost so badly

Americans are electing members of Congress, which is made up of the House of Representatives and the Senate. All 435 House seats are up for election. In the Senate, only 35 of 100 seats are being contested because senators serve six-year terms. This results tracker shows both the races being decided now and the 65 seats that are not up for election this year - 34 held by Democrats and 31 by Republicans.
The Democrats have swept to victory in the US midterm elections, taking control of Congress.
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