paso and dayton. beto o rourke missing the town fair to help his home town heal. julio castro claiming racism is a key issue. the president has brought this environment that has given rise to white nationalism. reporter: against an otherwise colorful backdrop, stern rebukes of president trump. we expect more out of our pre-schoolers now than we do the president of the united states. reporter: at a dinner put on by iowa democrats on friday night, joe biden weighed in. donald trump offers no moral leadership. he has no interest in unifying the country. reporter: five months from the iowa caucus, the tenor of this election serious. we need background checks. reporter: kamala harris on a campaign bus tour across the state. i think the american people are right to say look enough of the words. show me action. reporter: new polling shows a