On June 16, the Louisiana legislature passed HB 292. It sets up a single ballot for congressional candidates, which all voters use. This ballot is used in November. If anyone gets 50% or more of the vote, that person is elected. Otherwise, there is a run-off in December.
This system is somewhat different from the California and Washington state top-two laws. Louisiana does not prevent any candidate for Congress from campaigning during the summer and fall campaign season.
The Louisiana bill does not take effect until 2011.