The National Rifle Association is used to battling forces that criticize its fiery and unbending efforts to protect gun rights.

But as the group gathers for its annual convention this week, the NRA may be facing its toughest foe in decades: its own members.

NRA insiders and longtime observers describe an organization at war with itself over a central question: Has it strayed too far from its original mission of gun safety and outdoor shooting sports and become too political?

It is rare for the NRA to betray any hint of internal turmoil. But it erupted very publicly recently when the NRA sued its longtime public relations firm, Ackerman McQueen, accusing it of refusing to hand over financial records to account for its billings. In 2017 alone, the NRA paid the firm $40 million.

Ackerman McQueen has been by the NRA's side for two decades and has crafted its aggressive messaging, including the "From my cold dead hands" line uttered by actor Charlton Heston in 2000 as he vowed to resist any effort to take away his guns. The line became a rallying cry for gun owners around the country.

Ackerman McQueen also created and operates NRATV, the online channel whose hosts not only aggressively defend the NRA and its cause but often venture into political debates not directly related to firearms, such as immigration or diversity on children's TV. In its lawsuit, the NRA said some of its members have questioned NRATV's weighing in on "topics far afield of the Second Amendment."

The long history between the public relations firm and the NRA has made their potential parting of the ways all the more surprising to longtime watchers of the group.

"The battle in the NRA board that must have occurred with this breakup of a decades-long relationship must have been something," said Adam Winkler, a professor at the University of California Los Angeles School of Law and gun rights expert.

The strife is expected to be a dominant topic of conversation at the convention starting Thursday in Indianapolis, where President Donald Trump and Vice President Mike Pence will address the crowd on Friday. The NRA spent $30 million helping Trump get elected in 2016.

It has been a bumpy ride for the NRA over the past year.

The massacre at a high school in Parkland, Florida, last year created a groundswell of opposition to the NRA, driven by student-led protests over gun violence. Corporate America began pushing back, with some major retailers stopping gun sales and banks dropping discounts or certain services for NRA members and gunmakers.

More recently it was disclosed that Russian operatives tried to use contacts in the NRA to influence American elections. Democrats in Congress vowed to launch investigations into the gun lobby.

The NRA does not release detailed membership numbers but has repeatedly said in recent years that it has about 5 million members. The tax-exempt organization's filings with the IRS for 2016 and 2017, the most recent years available, show combined losses of nearly $64 million. The financial turmoil was seen as a key reason the NRA raised its dues last year for the second consecutive year.

Around the same time, the NRA saw its political influence wane during the 2018 elections and got outspent by gun control groups headed by former Rep. Gabrielle Giffords and New York Mayor Michael Bloomberg. More than a dozen NRA-backed congressional candidates lost in last year's midterms.

The NRA also faces regulatory pressures in New York, where the marketing of its line of insurance for gun owners involved in shootings was scrutinized. That legal action ultimately led the broker and underwriting firm for the insurance to pay millions of dollars in fines and abandon the program.

The NRA's charter was created in New York, and there are concerns that state officials may look for ways to strip it of its nonprofit status.

With the organization struggling financially, even some NRA stalwarts have begun questioning whether the millions spent on public relations and NRATV is worth the money.

One NRATV segment in particular seemed to be the last straw for some members: It took the children's show "Thomas & Friends" to task for adding some ethnically and gender diverse characters to its lineup of talking locomotives and other vehicles. The segment featured several trains wearing Ku Klux Klan hoods and sitting on flaming tracks.

It's unclear if the divide is so gaping that it will lead to the ouster of NRA leaders during the convention.

None of the more than two dozen board members contacted by The Associated Press would comment, with several saying they do not publicly discuss internal politics. Andrew Arulanandam, the NRA's managing director of public affairs, said recent reports of turmoil or financial troubles have been exaggerated and fueled by anti-gun forces.

Ackerman McQueen declined to comment.

Another question that could be answered at the convention is the fate of the NRA's president, retired Lt. Col. Oliver North, a central figure in the Iran-Contra scandal of the 1980s. He has a $1 million contract with Ackerman McQueen. That has raised alarm bells within the NRA about conflicts of interest.

John Crump, a longtime NRA member, firearms instructor and contributor to Ammoland, an industry publication, said he has never seen such a split within the NRA as exists now. But he is doubtful that any real change will take place.

"I know a lot of people want that, but I just don't see it happening," he said. "I think they have too much power right now. It's going to take a big revolt to get them out of power."

The strife has shades of the divisions that erupted in the 1990s when Neal Knox, an NRA leader in line to become its president, questioned the NRA's direction and spending and found himself ousted by those who supported Wayne LaPierre, the NRA's CEO with close ties to Ackerman McQueen.

Jeff Knox, a longtime NRA member and the son of Neal Knox, said the arguments today are similar to those from two decades ago. In a recent column, Knox questioned whether the NRA can survive.

"Could there actually be a group of directors within the upper echelons of the board who put the NRA first, above personal financial gain, cronyism and old loyalties?" he told the AP. "That would be a pleasant surprise."

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