The following states use runoffs for statewide or federal offices.

State	Notes
Alabama	50% threshold in primaries
Arkansas	50% threshold in primaries
Georgia	50% threshold in primaries and 50% threshold for general elections for certain statewide offices
Louisiana	50% threshold in federal primaries and conditional runoff with 50% threshold in "cajun primary" system for state elections like governor
Mississippi	50% threshold in primaries. Gubernatorial candidates must surpass 50% in general elections or the legislature selects the winners.
North Carolina	40% threshold in primaries
Oklahoma	50% threshold in primaries
South Carolina	50% threshold in primaries
South Dakota	35% threshold for primaries for federal office and governor
Texas	50% threshold in primaries
Vermont	No federal runoffs, but candidates for governor and certain other statewide offices must surpass 50% to avoid legislature electing winner.
Washington	State and federal system where two candidates advance from primary to general election.
Recently abandoned
Florida	Before 2006 elections eliminated primary runoff law after suspending it before  2002 and 2004 elections
Kentucky	In 2008 repealed runoff with 40% threshold that was for governor only, not for federal office