MADISON, Wis (Reuters) - Wisconsin voters head to the polls this week for the first of a series of special elections triggered by the bruising fight earlier this year over the union rights of public workers in the state.
Six Republican senators who supported the anti-union measure, and three Democrats who opposed it, have to defend their seats this summer as a result of recall efforts.
At issue is a new state law that curbs the power of public sector unions in the state, which triggered the biggest opposition demonstrations in the state since the Vietnam War.
If Democrats gain just three of the seats at stale once the final votes are cast, they will take control of the upper house and thwart Republican Governor Scott Walker's effort to pass his far-reaching legislative agenda. Republicans will continue to have a majority in the lower house, or Assembly.
On Tuesday, the first flurry of primary votes will take place, when the Democratic challengers seeking to unseat the six targeted Republican lawmakers are being forced to take part in a bizarre primary contest -- where they will be opposed by six Republicans who are running as Democrats.
It's a purposely confusing Republican tactic, legal under Wisconsin's unusual election rules, designed to delay the actual recall vote and give the targeted Republican lawmakers more time to raise money and campaign to defend their seats.
But on the eve of Tuesday's primaries, long-time election watchers say there was an outside chance the fake Democrats might beat the real ones in some races, meaning the seat would remain in Republican hands.
"If you get Republicans coming out and voting in the Democratic primary for the Republican candidate, anything could happen tomorrow -- especially if real Democrats don't take it seriously and don't mobilize" said Mordecai Lee, a professor of governmental affairs at the University of Wisconsin, Milwaukee who served in the state legislature for two decades.
Unlike many other U.S. states, Wisconsin has open primaries and no official party registration. So Republicans can run as Democrats and vote in Democratic primaries and Democrats can run as Republicans and vote in Republican primaries.
Normally, there's little reason for them to do that. But in the current situation, with turnout expected to be low in the rare mid-summer votes, the confusing tactic could prove decisive.
The nine recall elections scheduled between now and mid-August represent the single-largest wave of such votes in U.S. history and are a reminder of just how divisive the anti-union measures continue to be in this state.
The union law, which was passed by the Republican-controlled legislature and signed by Walker in March, eliminated most collective bargaining rights for public workers in the state and required them to pay more for pensions and health coverage.
Walker said the compensation and bargaining rights the public workers had enjoyed were unaffordable in an era of soaring state budget deficits and defended the measure as necessary to help the state fix its finances.
Democrats said the measure was a blatant effort to weaken public unions -- one of the Democratic Party's biggest financial supporters.
The fractious debate over the measure propelled Wisconsin to the forefront of a wider national political fight as Republicans who took control of many statehouses in the November 2010 midterm elections moved aggressively to shrink government and made reining in public unions a top priority.
(Additional reporting by David Bailey and Jeff Mayers; Writing by James B. Kelleher)