On Tuesday, Wisconsinites will decide the political fate of six Republican state senators who backed Gov. Scott Walker’s anti-union agenda. In order to regain the majority in the state senate, and check Republican power in Wisconsin, Democrats must recall three out of six GOP legislators tomorrow and successfully defend two Democratic legislators against recall votes next week.

Knock out three, hold two. Sounds manageable, right? However, as Craig Gilbert notes at the Journal Sentinel.com, U.S. voters have never recalled more than two state legislators in the same year in the entire history of recalls. Only 13 state legislators have ever been recalled, period. There are 16 legislators facing recall in Wisconsin right now. Then again, Gilbert notes, the Wisconsin race is unprecedented in many respects. This is the first time a state-level recall battle has become a national referendum. Money and media attention are pouring in from across the country. 

Andy Kroll of Mother Jones has assembled an invaluable election-eve cheat sheet, based on publicly available polling data and interviews with progressive insiders. By Kroll’s count, the Democrats have a clear lead in two races, the Republican is ahead in another, and three more are still too close to call.

This is uncharted territory. Anything could happen.