Gov. Scott Walker took the oath of office 18 months ago promising to be tough but compassionate as he acted swiftly and decisively to get Wisconsin back to work.

Now his job is at stake with a June 5 recall that will either make him the third governor in U.S. history to be ousted midterm or the first to survive such a vote. The race, in which Walker faces a rematch against Milwaukee Mayor Tom Barrett, is widely viewed as the most important this year nationwide other than the presidential.

Walker describes it as a test of political courage. He took on public sector unions and won, effectively ending their collective bargaining rights. But he never campaigned in 2010 on the collective bargaining issue, which sparked the recall movement. To his detractors, Walker's transgressions are so deep and wide there can be no solution other than immediate removal from office.