Mark Lamb holds the leading position in trader consensus for the AZ-05 Republican primary due to his strong name identification as former Pinal County sheriff, prior statewide candidacy, and endorsements including from Club for Growth, in a district vacated by Andy Biggs. Polls from late 2025 showed him ahead by double digits among likely Republican primary voters. Jay Feely and Travis Grantham register minimal support after both withdrew to pursue other races, leaving Daniel Keenan as the primary remaining challenger. Recent allegations of sexual impropriety against Lamb, reported in May 2026, along with related perjury claims and a cease-and-desist dispute, have introduced uncertainty into the race ahead of the July 21 primary. These developments have tempered Lamb’s implied probability despite his structural advantages in fundraising and visibility.