When the Senate Conservatives Fund recently passed over Republican Rep. Bill Cassidy in Louisiana and instead endorsed his primary opponent, Rob Maness, for Senate, it looked like the telltale early shots of a fierce Republican primary battle.

“(Maness) offers voters a compelling choice over Sen. Mary Landrieu because he's not a Washington insider,” Senate Conservatives Fund Executive Director Matt Hoskins said in a statement at the time.

It’s not yet clear how much money the Senate Conservatives Fund will spend on behalf of Maness, a newcomer to Louisiana politics and to the state itself, but the group’s entrée into the race was enough to put Cassidy’s campaign on edge — and to bring Democrats circling.

"Republicans are seeing what voters across Louisiana have learned about Bill Cassidy since he began his listless campaign for Senate – that he's not someone they can trust to come clean about where he stands or fight for Louisiana families,” Andrew Zucker, a spokesperson for Louisiana Democrats, said in a statement following the SCF’s announcement.

But there is less uncertainty about who will be the top Republican contender to face Landrieu, D-La., than this commotion would suggest.

Louisiana is no North Carolina, where a far more raucous Republican primary is beginning to develop. There, the candidate backed by the National Republican Senatorial Committee, statehouse Speaker Thom Tillis, is facing two notable Republican challengers -- one of whom, Greg Brannon, has been endorsed by Sen. Rand Paul, R-Ky.

For Cassidy, by comparison, a path has been cleared by Louisiana Republicans, who see him as their best chance to beat Landrieu.

He was endorsed early by Sen. David Vitter, R-La., the state's de facto Republican leader, and backed by other GOP members of the state's congressional delegation.

Those lawmakers in June held a fundraiser at the National Republican Senatorial Committee headquarters for Cassidy — implying the committee’s approval of Cassidy over all other Republican comers.

But the biggest endorsement for Cassidy may have come last week, when conservative state Rep. Alan Seabaugh, of Shreveport, long rumored to have been weighing his own bid for Senate, announced he instead would throw his support behind Cassidy.

“At this point, the entering of another Republican candidate into the U.S. Senate race would serve only to divide Republicans and conservatives at a time in which we need to all be working together to rid Louisiana and the U.S. Senate of Mary Landrieu once and for all,” Seabaugh wrote in a letter announcing his decision.

Now, Cassidy’s biggest Republican adversary might be — himself.

As he attacks Landrieu for being too liberal or too close to President Obama, Cassidy will be challenged to explain some of his own more moderate positions, including support for health care exchanges under some circumstances.

In an interview in August, Cassidy, who is a doctor, said Utah and Massachusetts have adopted health care models that are “fantastic.” His office clarified last week that he was emphasizing support for non-federalized health care systems.

Cassidy has also broken with his party when, during a congressional-race debate in October 2008, he expressed support for the federal bailout of the financial industry, commonly referred to as TARP. Landrieu voted against that measure as a senator.

“The bill had problems, but having said that, sometimes you have to accept problems for the greater good,” Cassidy said during the debate. “I would have voted for that bill. And it was for jobs. It was for small business, and it was for retirees.”

A spokesperson for Cassidy said he stands by that statement today, but that his verbal support was “different than a vote.”

“There are so many more issues that are prevalent in people’s minds,” the spokesperson said.

If Republicans have been lukewarm to support Cassidy, his fundraising numbers have not reflected it. In fact, he brought in more money than either of Landrieu’s previous Republican challengers at this stage of an election, with nearly $700,000 in the third quarter and $3.4 million on hand.

Maness, on the other hand, finished the quarter with less than $17,000 on hand.

And, because of Louisiana’s unique open primary system, the SCF’s support for Maness might ultimately help Cassidy: As long as Landrieu does not receive a majority of votes in the primary, the top two candidates are forced into a runoff in December 2014.