The Swedish Social Democratic Party has played a leading role in Swedish politics since 1917, after the Reformists had confirmed their strength and the left-wing revolutionaries formed their own party. After 1932, most governments have been dominated by the Social Democrats. Only five general elections since World War II—1976, 1979, 1991, 2006 and 2010—have given the assembled bloc of centre-right parties enough seats in the Riksdag to form a government.