Prime Minister Gordon Brown said on Wednesday he would overhaul the scandal-hit parliament and take more steps to secure an economic recovery if his Labour Party defied the polls and won the May 6 election.
His plan for sweeping political reforms might appeal to the Liberal Democrats, whose support Labour may need to form a government if it fails to secure an outright majority in what looks like the closest race in 20 years.
Labour has trailed the Conservatives in the opinion polls since January 2008, but the gap has narrowed and the latest surveys point to a result in which no single party would have an overall parliamentary majority.
The prime minister said voters would be given a say on constitutional reforms in a referendum before October 2011, including changing how MPs are elected and the possibility of an elected upper chamber.
The proposals are in part a response to public disgust with politicians after many MPs abused their expense allowances by claiming money for items such as a duck house or dog food.
"I would ... take no joy in victory if it comes without a mandate to get rid of the old discredited system of politics," Brown said in a speech a day after setting the election date.
He called for parliaments to be elected for a fixed term, instead of the current system where the prime minister can call an election at any time up to a five-year maximum.
The measures will be seen as an attempt to woo the Liberal Democrats, who have long argued for political reform, including a switch to proportional representation.
But the Liberal Democrats dismissed the proposals.
"How on earth are we supposed to believe anything that Gordon Brown says about political reform when they've done nothing for 13 years?" said Liberal Democrat leader Nick Clegg.
ECONOMIC RECOVERY
Conservative leader David Cameron used a bruising parliamentary session to accuse Brown of wrecking the economic recovery with plans to raise payroll taxes.
With the parliamentary chamber in uproar, Brown hit back by accusing the Conservatives of putting growth and jobs at risk with their plans for public spending cuts to reduce the gaping budget deficit.
Arguments about the best way to nurture the hesitant economic recovery are set to dominate the election campaign, in which the Conservatives are trying to end 13 years of Labour rule.
"This prime minister would wreck the recovery by putting a tax on every job, on everyone earning over 20,000, a tax on aspiration, a tax on every business in the country -- this government would wreck the recovery," Cameron said.
Several business groups and 38 large employers have backed the Conservatives' opposition to a planned rise in National Insurance, a payroll tax. Brown said the Conservatives had "deceived" them.
Brown said that to withdraw six billion pounds from the economy, as he says the Conservatives plan to do, would put jobs, businesses and growth at risk. "We cannot cut our way to recovery but we could cut our way to double-dip recession," he said.
Brown said in a Channel 4 News interview that his party would make an election pledge to hold the basic income tax rate at 20 percent.
