 The nonpartisan blanket election was never used for presidential primaries in Louisiana because national party rules forbid it.It has been used for congressional elections from 1978 to the present, with a brief interruption in 2008 and 2010.Starting in 1978, the Louisiana legislature changed the rules for conducting US House and Senate elections, changing them to the nonpartisan blanket primary format, with primaries in late September or early October, and general elections on the federal election day in November.