Both major political parties are preparing for a state-by-state legal battle over how Americans can vote during the coronavirus outbreak. The dynamic played out in Wisconsin this week when judges initially held up Tuesday’s election, changed its rules and then put it back on shortly before polls opened. Democrats argue that states need to make voting easier and provide more opportunities to vote by mail during the pandemic to prevent the virus from spreading. They say they’re ready to sue to force that. Republicans say Democrats just want to loosen rules to help them win elections.