Ruben Gallego is a progressive Democrat and Marine combat veteran who served four tours in Iraq before entering politics as a fierce advocate for veterans' rights and working-class families. Known for his outspoken criticism of corporate influence in politics and his support for aggressive climate action, he built a reputation in the House as one of the more liberal voices willing to challenge both Republican opponents and moderate Democrats. Gallego made headlines by launching a primary challenge against Senator Kyrsten Sinema before she became an independent, positioning himself as the anti-establishment alternative who would reliably support Democratic priorities. His working-class Latino background and military service have made him a compelling figure for Democrats seeking to rebuild their coalition in increasingly competitive Arizona.