Tensions within the Democratic Party over age, representation and experience have roiled a special election primary in southwest Arizona, where a young, social media-savvy activist is taking on the daughter of Rep.

The Democratic primary to fill the seat vacated by the death of Representative Raúl M. Grijalva in Arizona’s deep blue Seventh Congressional District in Tucson will be a contest between legacy and change.

Grijalva, 54, sees it as a race of experiential divides, not generational ones. Her election would also carry symbolic weight as Grijalva would be the first Latina to represent Arizona in Congress. Hernandez,