“It reached its height in the mid to late ’80s, especially at the federal level, [with] people voting [differently] for president and Congress,” Barry C. Burden, a professor of political science at the University of Wisconsin-Madison, told Vox. But as political polarization, the decline of local news, and the nationalization of local politics have increased in the past two decades, split-ticket voting has been dying a slow death.
“Very few states [have] senators of different parties, and they’re even elected in different years,” Burden, who co-wrote a book on this history, said. “Even the number of split Senate delegations, where senators are from different parties, is now at a relative low.”