A budget battle in the US state of Wisconsin that brought tens of thousands of protesters on to the streets has touched off a national political firestorm that could have implications for the next presidential election.
Some 70,000 people, including union members from neighbouring states, flooded the state capital Madison on Saturday, protesting against benefit cuts proposed for government workers and an attack on union bargaining rules by the right-wing Governor.
And thousands were again expected to brave snow and freezing temperatures at a midday rally yesterday, on the sixth consecutive day of protests.
The action foreshadows a political debate that is expected to grow in intensity over the next two years, as state governors propose unprecedented budget cuts and Democrats accuse their Republican rivals of using budget crises as an excuse to attack the Democrats' union base.
Wisconsin has hit national attention not just because of the swelling crowds of protesters, which led many commentators here to liken the scenes to those in the Middle East, but also because it is an early test of the political parties' ability to get supporters fired up ahead of the next elections in November 2012. The right-wing Tea Party movement assembled its own protesters to support Governor Scott Walker's proposals on Saturday, including their hero of the 2008 presidential campaign, Joe the Plumber. Meanwhile the grassroots group assembled by Barack Obama for that presidential campaign was urging its supporters to make their voices heard against the plan.
President Obama himself weighed in on the side of public employees, saying "they are our neighbours, they are our friends... they make a lot of sacrifices and it is important not to vilify them". Some of Governor Walker's proposals "seem like an assault on unions", he said.
Putative Republican presidential candidate Sarah Palin sent her own declaration of support to the Tea Party protesters in Madison, framed as a message to the other side: "Union brothers and sisters, this is the wrong fight at the wrong time."
Wisconsin is seen as a key battleground for the 2012 election. The state was won by President Obama and he is unlikely to be able to retain the White House if he loses its support.
Governor Walker, who was elevated to the chief executive job when Republicans swept last November's midterms, proposed a budget bill that requires the state government's 300,000 workers to pay more for health benefits and bigger pension contributions in order to help fill a $3.6bn (£2.2bn) budget deficit. The measure also includes a wide assault on the power of public -sector unions, including a ban on collective bargaining over benefits, an end to automatic deductions of union dues and the introduction of annual votes on union recognition.
In co-ordinated moves, when the protests began last week with teachers and firefighters storming the capitol building, 14 Democrat statehouse senators moved over the border into Illinois so that there could be no quorum for a debate on the law.
Protesters have repeatedly occupied the rotunda of the capitol every day since, chanting "Kill the bill".
Republicans sense that, after years of creeping cuts to pensions and benefits in the private sector, public sympathy for public-sector unions has been significantly weakened and Governor Walker signalled yesterday that he would not be backing down.
Unions have said they would swallow the benefits and pension contribution hikes, but not the assaults on union rights, but the Governor said giving workers the chance to opt out of union membership meant they could redirect membership fees to help fund pensions and health insurance.
"As powerful as the voices are in the capitol, I have to make sure they don't overpower the voices of the people I was voted in to represent," he said. "For decades we had leaders, Republicans and Democrats, pushed off the problems. Now there's no place to push them off to.
"We're going to make tough decisions now. We have to, to get our budget balanced."
Across the political spectrum, as budget deficits have ballooned at all levels of government, candidates have vied to propose the toughest cuts.
However, it is at the state level where the biggest austerity measures are being imposed and where both political strategists and economists are watching in order to judge their effects.
Strategists are looking to see what size and what kind of cuts risk provoking a public backlash of the kind seen in Wisconsin. Economists, meanwhile, worry that pay cuts and layoffs could set back the recovery from recession.