A Republican congressional candidate backed by President Donald Trump is facing explosive backlash after leaked messages revealed racist exchanges with the leader of a controversial armed border vigilante group.

And the revelations are sending shockwaves through Arizona politics.

According to a report from The Arizona Republic, former Pinal County sheriff Mark Lamb — now running for Congress in one of the nation’s most politically charged races — exchanged racist jokes in private Facebook messages with Nick Steele, a figure connected to the extremist border group Border Narcotics Intelligence.

The leaked messages reportedly date back to 2016 during Lamb’s first campaign for sheriff.

And critics say the contents are devastating.

According to the report, Steele told Lamb that members of his vigilante organization were supporting Lamb’s campaign efforts.

Then came the exchange now igniting outrage nationwide.

“BNI guys work like (N-words),” Steele allegedly wrote.

Lamb reportedly responded with laughing emojis before joking back:

“So you don’t do anything?”

Steele then attempted to clarify the comment.

“LOL No we work like (N-words) cuz it’s the right thing to do…” he allegedly replied.

Lamb then reportedly praised the group.

“You guys do work hard,” he wrote. “I’m impressed! And grateful!”

The revelations immediately triggered fierce backlash because Border Narcotics Intelligence has long faced accusations of extremism, vigilantism, and operating as a private border militia outside traditional law enforcement oversight.

The organization claims to patrol border regions independently in support of anti-immigration operations.

Now critics are questioning how deeply connected Lamb may have been to the group during his political rise.

Lamb did not publicly deny the messages in the report.

According to The Arizona Republic, his campaign declined to elaborate on the relationship between Lamb and the organization or explain what role the group may have played in supporting his campaign.

The controversy grew even more politically explosive after a former Black campaign staffer, William Hubbard, reportedly confirmed that Lamb apologized shortly after the exchange occurred.

But for many critics, the apology itself only reinforced the authenticity and seriousness of the messages.

The scandal arrives at an already turbulent moment for Lamb’s congressional campaign.

He is currently running for the seat being vacated by hardline conservative Andy Biggs, a powerful figure within the far-right House Freedom Caucus.

And Lamb has already faced mounting controversy from previous allegations involving nude photos and accusations that he attempted to intimidate recipients into silence by threatening legal consequences.

He also previously drew criticism after describing detention standards for immigrants as “irritatingly high” — remarks that immigration advocates blasted as dehumanizing and extreme.

Now, the leaked messages are adding fuel to accusations that Lamb’s political image has been deeply intertwined with extremist rhetoric and hardline anti-immigration movements from the beginning.

Supporters of Lamb have defended him online, arguing the messages were old, taken out of context, and part of private joking conversations from years ago.

Critics reject that defense entirely.

For them, the issue is not merely offensive language.

It’s the broader pattern.

A Trump-backed candidate tied to armed border vigilantes.

Racist exchanges involving slurs.

Past controversies involving immigrants and intimidation allegations.

And now a congressional race suddenly consumed by questions about extremism and character.

The controversy also reflects a larger reality increasingly shaping modern Republican primaries:

Candidates aligned closely with Trump and MAGA politics are often rewarded, not punished, for hardline immigration rhetoric and confrontational anti-establishment branding.

But scandals involving racism and extremist ties still carry enormous political risks — especially in competitive general elections.

Whether the leaked messages ultimately derail Lamb’s campaign remains unclear.

But Wednesday’s revelations transformed the race overnight.

Because what was already a controversial candidacy has suddenly become something much darker.

And for Republicans now preparing to defend another Trump-backed nominee, the timing could hardly be worse.