Louisiana's switch from an open primary for congressional elections means changes in who can vote in the Sept. 6 Republican primary.

Wednesday is the deadline to register to vote in the Sept. 6 election -- and also to be registered as a Republican if you want to vote in the Republican primary.

Twenty-year incumbent Republican Congressman Jim McCrery is not seeking re-election, and a wide-open election is emerging.

If you plan to vote for one of the three Republican candidates, you have to be a registered Republican. The Republicans in the race are John Fleming, Chris Gorman and Jeff Thompson.

You don't have to be a registered Democrat to vote for Willie Banks, Paul Carmouche, Artis Cash or John Milkovich in the Democratic primary.

"If you're (registered) 'no party' or a member of a non-recognized party, then you are invited by the Democrats to vote in their primary," said Caddo Registrar of Voters Ernie Roberson, "but you cannot vote in the Republican primary."

In Louisiana, the Libertarian, Reform and Green parties are all considered recognized political parties, so their registered members can't vote in the Democratic primary.

The same rules apply if a run-off is needed in the Republican or Democratic primaries.

The run-off election is Oct. 4, the same day as local and judicial elections, which continue to be an open primary -- meaning you can vote for any candidate regardless of party affiliation.

"It's going to be a very confusing election," Roberson predicted.

To further complicate matters, if you miss Wednesday's deadline to switch your party affiliation, the deadline to do it for the Oct. 4 primary runoff is Sept. 4. So if you go to vote in the Sept. 6 primary and realize you are not a member of the political party you prefer, you will have missed the deadline to switch parties it for the Oct. 4 election.

More information is available through your local registrar of voters office.

Early voting for the Sept. 6 primary is Aug. 23-30, except Sunday.