The bitter mudslinging campaign for Louisiana governor will come to a head Saturday, closing out a contest that's dredged up one candidate's past with prostitutes and most recently turned on whether to admit Syrian refugees into the state.

Once seen as the frontrunner in the race, Sen. David Vitter was hammered by his GOP rivals over his involvement in the D.C. Madam" scandal. Named as a client in in 2007 the prostitution ring, he apologized back then for a "serious sin" with his wife by his side and won reelection three years later.

His opponents resurrected the scandal and used it to question his social conservative bonafides. Vitter escaped into the runoff, but his Democratic challenger, state Rep. John Bel Edwards seized on the questions about his moral character.

In a particularly brutal ad, Edwards contrasted his military service with Vitter, charging that the Republican chose "chose prostitutes over patriots" by skipping a vote to honor fallen servicemen to take a call from the prostitution ring.

But after last week's terrorist attacks in Paris, the tone and topic of the race shifted. Trailing, Vitter launched an ad that used footage of the attacks and called for a halt of Syrian refugees into Louisiana, fearing that ISIS sympathizers could infiltrate.

He accused Edwards of believing that immigration from the region should still be allowed after the Democrat wrote that he would work to "accommodate refugees" in a Facebook post; that was later edited to indicate he supported a "pause" due to security concerns. And a pro-Edwards superPAC fired back with an ad saying it was Vitter who had in the past downplayed the threat from Syria and skipped Senate hearings on the issue.

The two mean didn't mince words on the issue during their final debate: Edwards called Vitter's attack "desperate" and the Republican called him "John Bel Come Lately" on the issue.

The shift to security concerns could be helping Vitter, though. One independent poll showed the Republican nearly closing the gap with Edwards.

If Vitter does pull off a win, it would further underscore just how much voters have soured on Democrats in the South. In 2014, they lost four Senate seats in the region, including in Louisiana, along with many House races.

Earlier this month, it seemed like things were looking up for the party. Polls predicted Democrat Jack Conway would hold the open seat contest for Kentucky governor, but instead Republican nominee Matt Bevin easily captured the seat for just the second time in forty years for the GOP.

Edwards is the type of Democrat that should be able to win in the conservative state — his ads have stressed his opposition to abortion and support for gun rights, and he's also opposed to gay marriage. And one of Vitter's former opponents, Republican Lt. Gov. Jay Dardenne, even crossed parties to endorse Edwards.

But Republicans have looked to tie the Democrat to President Obama at every turn — a strategy that have worked time and again, and did in Kentucky too. The state still leans Republican, and if those voters come out for Vitter while Democrats and African-Americans that Edwards needs don't show up, the partisan edge could be too much to overcome. But if conservatives stay home, Edwards could prevail.

Just how off the polls in the Bluegrass State were too have to have Democrats worried for the Louisiana results, especially given the shift to security concerns and away from conversation about Vitter's personal life.

A few weeks ago, most everyone expected Edwards would pull off the upset. But now it wouldn't be as much of a surprise if Vitter does escape and win the race.

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