The mud is starting to fly in Louisiana in a fierce Republican Member-vs.-Member race that pits a close ally of Speaker John Boehner’s against a fiery tea-party-backed rookie.

On paper, it’s Rep. Charles Boustany’s race to lose. As chairman of the Ways and Means Subcommittee on Oversight, Boustany commands considerable fundraising resources and holds a $1 million edge in cash on hand.

But Rep. Jeff Landry is waging a lively battle, fighting off Boustany’s attacks and winning endorsements from the right.

The race has the feel of a GOP primary, but five candidates — three Republicans, a Democrat and a Libertarian — will be on the ballot Nov. 6, given Louisiana’s campaign rules. If no candidate gets a majority of the vote, the top two candidates would face off in a runoff election in December.

The rules are helping Landry.

Boustany could bleed votes to Ron Richard, the Democratic candidate who filed a statement of organization with the Federal Election Commission on Aug. 27. “The votes [Richard] takes away would tend to be Boustany’s,” said John Maginnis, the publisher of LAPolitics Weekly.

And a low-turnout runoff would “not be in Boustany’s interest,” Maginnis said, because the activists that would show up to vote are siding with Landry.

A recent episode shows how Boustany is losing among the hard right, including from a tea party chapter in the heart of his political base that is teaming up with Washington, D.C.-based FreedomWorks to help Landry with phone banks and other efforts.

At a Sept. 17 meeting at Fezzo’s Restaurant in Crowley, La., Boustany made a hard pitch on how conservative he is to members of the Acadia Parish Republican Executive Committee, touting his support for gun rights and an instance where he broke to the right of former President George W. Bush.

But the pitch fell flat, particularly on the Second Amendment. “We knew he grew up downtown in a rich household — we just weren’t buying it,” one elected member of the committee said. Ten minutes after Boustany left, the board voted to endorse Landry, according to the source, who added that Boustany’s pitch actually cost him votes.

Behind the scenes, many of the heavyweights in the Republican establishment are backing Boustany, Maginnis said.

Boustany has drawn fire for comments he made in 2011 that he wouldn’t again sign a pledge organized by Grover Norquist, the president of Americans for Tax Reform, not to raise taxes. “We have to have the flexibility to do the right thing for the American people,” he told the Lafayette Advertiser editorial board in August 2011.

Joyce Linde, the president of Geaux Free TPL, a tea party chapter in Lafeyette, said Landry’s embrace of the Norquist pledge was a top reason her group sided with Landry.

However, Boustany is still listed as a signer of the pledge. He has spoken to Norquist, understands the pledge is still binding and won’t vote to raise taxes, according to a spokesman.

Both campaigns say they are aghast at how dirty the race is becoming, but in all likelihood, the mud is just beginning to fly.

“This race is a typical Jeff Landry production — from mud-slinging to stolen signs to behind-the-scenes arm-twisting and sham endorsements,” said John Porter, Boustany’s campaign manager.

“This is typical of Mr. Boustany; hiding behind others and focusing on inside baseball campaign tactics instead of the critical issues affecting the nation,” fired back Brent Littlefield, Landry’s political consultant.

Some of the heaviest artillery has been fired by Boustany, who charged in television advertisements and mailings in September that Landry’s businesses had failed to pay their taxes on time.

In Louisiana, sheriffs collect taxes, and two of the local sheriffs came to Landry’s aid, saying that the taxes were paid for in a “timely manner.” Boustany’s campaign produced records showing that Landry’s businesses had in fact paid property taxes weeks late, but the backing of the sheriffs may have insulated Landry from the attack.

“It didn’t sound like it worked,” Maginnis said.

Boustany is out with a new mailer that savages Landry for voting to adjourn Congress without dealing with the pending “fiscal cliff,” a series of expiring laws that will result in spending cuts and higher tax rates next year if left unaddressed. However, Republicans control the House, and Boehner said recently that dealing with the fiscal cliff before the post-election lame-duck session might not be advisable.

One question for Landry is whether his fiery temperament will continue to work for him politically.

In September 2011, for example, Landry arrived at a local Interior Department office unannounced, demanding to meet with top officials about drilling permitting issues. Landry later accused the employees at the office of acting “like the CIA and Gestapo” to the New Orleans Times-Picayune.