Multiple groups of states formed compacts in an attempt to coordinate some of their responses. On the West coast: California, Oregon, and Washington state; in the Northeast: Massachusetts, New York, New Jersey, Connecticut, Delaware, Pennsylvania, and Rhode Island; and in the Midwest: Michigan, Ohio, Wisconsin, Minnesota, Illinois, Indiana, and Kentucky.[1][2][3]
There was a link between public health outcomes and partisanship between states. At the beginning of the pandemic to early June 2020, Democratic-led states had higher case rates than Republican-led states, while in the second half of 2020, Republican-led states saw higher case and death rates than states led by Democrats. As of mid-2021, states with tougher policies generally had fewer COVID cases and deaths.[4][5] Thousands of US counties also initiated their own policy responses to the pandemic, resulting in significant variability even within states.[6]