Now that the voting has started, the presidential field is finally starting to winnow itself. Since Monday’s Iowa caucuses, one Democrat and three Republicans have suspended their campaigns, and more could follow after next week’s New Hampshire primary.

Meanwhile, Louisiana’s U.S. Senate primary, on the ballot for the same day the nation elects its next president, is heading in the opposite direction.

The race picked up a sixth major candidate last week, and more could well follow.

And why not? U.S. Sen. David Vitter’s imminent retirement creates a rare opening for ambitious fellow Republicans who know the state’s partisan leanings tilt their way. And the profusion of GOP hopefuls gives Democrats at least a bit of hope that they can sneak in and pull off another big surprise, as they did when John Bel Edwards cleaned Vitter’s clock in last year’s governor’s race.

First, a cautionary note for any Democrats who may have let Edwards’ victory go to their heads: Despite the new governor’s unexpected victory, there’s no reason to think this is a trend in the making. Louisiana remains stubbornly Republican in national races, and voters are more likely to stick to their partisan leanings when voting for Senate than the Governor’s Office, where less divisive issues can prevail.

Beyond that, Edwards had distinct advantages, including his military background, conservative stands on some major social issues that blunted the impact of his populist leanings on social justice and fiscal matters and crackerjack advertising efforts from his own campaign and a couple of sympathetic super PACs. He was the only Democrat running against several Republicans, which pretty much guaranteed him one of two runoffs positions. And because all his GOP rivals hoped to face him rather than another Republican, nobody really attacked him during the long primary season.

And Vitter had some unique weaknesses, starting with the painfully obvious one: his past dalliances with prostitutes. Add to that harsh judgmental and ideological streaks, stylistic similarities to the deeply unpopular ex-Gov. Bobby Jindal and a slew of old and new enemies who were happy to help bury him, and you’ve got the makings of an epic collapse. By staging brutal attacks against two more moderate Republicans in the primary, Lt. Gov. Jay Dardenne and Public Service Commissioner Scott Angelle, Vitter’s team had managed to keep either from gaining enough momentum to squeeze Vitter out of a runoff spot. But it was all downhill from there.

Still, Louisiana’s open primary system can create strange dynamics, and the first Democrat hoping to recreate the Edwards magic announced her plans last week. Lawyer Caroline Fayard has never held office, but she built something of a name in a losing run for lieutenant governor a few years back, and she has close ties to big-money trial lawyers. If she remains the only major D on the ballot — a big if — she’d have a good chance of claiming one of two runoff spots. If not, chances of an all-Republican runoff increase exponentially.

At this point, the Republican side is shaping up to look something like this year’s presidential field by virtue of sheer numbers.

Two announced candidates, U.S. Rep. John Fleming and Col. Rob Maness, are running in the Tea Party lane. U.S. Rep. Charles Boustany shares the establishment side of the ledger with five-term state Treasurer John Kennedy, who is nevertheless trying to position himself as an unlikely outsider. Angelle may run too, which would give us a third more mainstream candidate and complicate Boustany’s attempt to own the Acadiana base they share.

Also in the mix is an independent, former Alcohol and Tobacco Control Commissioner Troy Hebert.

Still more candidates are talking about running, so the picture may get even murkier before Election Day. Republicans have the edge, but there’s no obvious party leader who might be able to cull the field and unite behind a chosen candidate — ironically, Vitter is the one who used to play that role — and unlike in the presidential race, there will be no ongoing primary process to create order because the first round of voting doesn’t happen until Nov. 8.

So if you’re one of the few people who’s actually been enjoying the presidential free-for-all, take heart. The chaos, particularly on the GOP side, will eventually end. But you’ll always have Louisiana. At least through November.

Stephanie Grace can be contacted at Follow her on Twitter, @stephgracenola.