Duke is the same age and determined to vote, because in his family, being politically active is expected. But his mind is really on his band's first paid gig tonight and he just wants to get in and get out. However, that's not how it turns out. He's not on the rolls and when Marva overhears his plight she takes him under her wing and drives him from place to place trying to get him his vote. Through a day filled with every possible (and sadly familiar) set back from closed polling places to ballot shortages and long lines, the two young people become friends and more as they share the quest to participate in the democratic process.
It's a clever setting for a YA romance that would have made an excellent short story. Even as a novella, it probably would have had room for all the politics that Colbert puts in (voter suppression, BLM, interracial marriage, racial identity, etc.). As a novel though the material is too thin. So, Colbert throws in dead siblings, failed relationships, and even a missing cat -- much of which seems distracting and immaterial to the story. Sometimes a great story doesn't need to be a novel, but I guess it was a more commercial proposition to make it so.