The conflict and Twitter battles arrived in Minnesota well ahead of President Donald Trump's touchdown in the state.
Trump traded Twitter insults with the Minneapolis mayor over who should pay more than $500,000 in security costs for Thursday's rally at a downtown arena.
He denounced Jacob Frey as a "Radical Left" lightweight and blasted the Democrat for a police policy banning officers from wearing their uniforms in support of political candidates. He sprinkled in a reference to his favorite foil the city's Rep. Ilhan Omar just for good measure.
"Yawn," Frey tweeted back. "Welcome to Minneapolis where we pay our bills, we govern with integrity, and we love all of our neighbours."