Mark Lamb, the former Pinal County sheriff backed by President Donald Trump, won Arizona's 5th District Republican primary Tuesday, overcoming allegations of sexual misconduct that his opponent made central to the campaign. Lamb will face no Democrat in November in the deep-red Phoenix-area district and is heavily favored to replace Rep. Andy Biggs (R-Ariz.), who is running for governor.
Daniel Keenan, a self-funding challenger, spent nearly $2 million of his own money attempting to make Lamb's alleged abuse of power an issue in the race. Despite these efforts, Trump reinforced his endorsement of Lamb in mid-July, and Arizona-based Turning Point USA maintained its support throughout the controversy. Lamb has denied all allegations through a spokesperson who called them false claims from long-discredited political opponents.
What the Right Is Saying
Conservative supporters say Lamb's win validates that voters prioritize policy positions over media-driven scandal cycles. The Republican National Committee and multiple pro-Trump groups pointed to Lamb's record as a vocal critic of Biden administration immigration policies as why he earned the president's backing. Turning Point USA officials argued that years of conservative advocacy on border security and Second Amendment rights matter more to primary voters than unverified allegations.
Republican commentators noted that Keanan's heavy spending failed to move voters, suggesting that money alone cannot overcome incumbent-style advantages provided by a presidential endorsement. They characterized the race as evidence that Trump's electoral coalition prioritizes alignment with his policy agenda over other considerations.
What the Left Is Saying
Progressive critics argue that Lamb's victory demonstrates how Trump's endorsement can insulate candidates from accountability for serious personal conduct allegations. The Arizona Republic published a multi-part investigation in May detailing allegations from multiple women, including Jillian Stannard, who accused Lamb of encouraging her husband to have sex with other women and allegedly threatening consequences when she raised concerns with religious leaders. Screenshots obtained by the Republic suggested Lamb, as then-sitting sheriff, threatened to leverage Arizona's revenge porn law against another woman, Tammy Peacock.
Democratic strategists note that while this district is solidly Republican and no Democrat will compete in November, the race signals broader questions about primary electorate standards. They argue that voters deserve candidates whose personal conduct aligns with their public service records, particularly in law enforcement roles where trust is paramount.
What the Numbers Show
Keenan self-funded approximately $2 million for his campaign, an unusually high amount for a congressional primary challenger. Lamb's campaign relied primarily on outside support from Trump-aligned political action committees and Turning Point USA rather than personal contributions. The 5th District has voted Republican in every recent election cycle, with Cook Political Report rating it R+15, making it one of the safest GOP seats in Arizona. Turnout figures for Tuesday's primary have not yet been released by the Maricopa County Recorder's Office.
Lamb served as Pinal County sheriff until 2024, giving him name recognition and law enforcement credentials that resonated with conservative voters in the district. Trump first endorsed Lamb for the seat last year, predating the May allegations by several months. The president's decision to reinforce his endorsement in mid-July, after the scandal became public, demonstrated continued confidence in Lamb's viability.
The Bottom Line
Lamb enters November's general election as a heavy frontrunner in a district that has not elected a Democrat in recent cycles. His victory underscores the continuing electoral weight of Trump's endorsement within the Republican primary electorate and suggests that allegations of personal misconduct face significant hurdles when met with high-profile backing. Democrats have declined to field a candidate, making the November contest largely symbolic for partisan purposes but notable as a test case for how scandal-affected candidates perform in competitive Republican primaries.
Republicans will point to Lamb's win as evidence of party unity around Trump's chosen candidates regardless of external criticism. Democrats and ethics watchdogs say they will continue monitoring Lamb's candidacy ahead of the general election, though without a major party challenger, their leverage is limited.