Britain's opposition Conservatives pledged to cut public spending to rein in a huge budget deficit and called for a sweeping overhaul of the economy as they kicked off their campaign for this year's election Saturday. The Conservatives, favorites to win the vote, stole a march on Prime Minister Gordon Brown's Labour Party by announcing they were going into campaign mode, even though the election could still be five months away. “We are starting our campaign to win the general election today,” center-right Conservative leader David Cameron said in a speech in Oxfordshire. Cameron made clear that the main election battleground will be the economy and how to rein in government borrowing forecast to reach 178 billion pounds ($285 billion) this year. The fast-growing national debt was “the greatest single risk to sustained economic recovery,” Cameron said. “That's why we've been clear about our intention to cut public spending.” Beyond that, he said, “to have a hope of competing in the decades to come, our economy needs a complete overhaul.” “We need to build an enterprise economy... We need change right across the board: tax, regulation, banking infrastructure,” he said.