LONDON (Reuters) — As Britain’s longest-serving Chancellor of the Exchequer in 200 years, Gordon Brown will hope he does not become one of its most transient prime ministers.Last week’s local elections underlined the challenge facing the 56-year-old Scot who is preparing to take over from Prime Minister Tony Blair after 10 years directing economic policy.

The Conservative Party captured 40 percent of the vote last week and a similar result in the next general election, expected in 2009, could put them back in power and make Brown’s stay in 10, Downing Street the shortest since the 1960s.

Brown’s capture of the top job should give the Labour Party’s ratings a fillip — new leaders usually do that.

But the polls suggest voters are tired of Labour and dismayed by Blair’s prosecution of the Iraq war and a series of scandals suggesting financial impropriety.

“Gordon’s biggest challenge is how to present him taking charge as a new start and give energy, impetus, momentum and fresh vigour not just to government, but also to Labour,” said Alastair Newton, senior political analyst at Lehman Brothers.

“Gordon as much as Tony is parent to the Labour project and has presided over much of their policy for the last decade.”

Brown aides promise a new side to their man once he becomes leader. Freed from the confines of his Treasury brief, Brown will shake off his reputation for dullness, they say.

The Conservatives are led by 40-year-old David Cameron, who is still relatively new in the job, and Brown’s opponents will make Brown’s often brooding exterior a point of attack.

“They’ve been saying we’ll see a changed man for a year,” one Conservative shadow Cabinet member told Reuters. “We’re on the up.”

One of Brown’s first actions on moving into Downing Street will be to appoint his Cabinet and make a break from the Blair era by getting new, younger faces around the table.

Trade and Industry Secretary Alistair Darling looks on course to be the new finance minister and more junior ministers like Yvette Cooper and her husband Ed Balls, Brown’s right-hand man, are also in line to get Cabinet posts.

Experts predict a range of populist measures in the early weeks of a Brown premiership as he seeks to woo voters back to the Labour fold.

“Expect him to come back to the Labour Party in October with some funky new ideas, such as free prescriptions on the National Health Service and free health care for the elderly,” said London School of Economics professor Patrick Dunleavy.

“I think he’ll unveil some fairly left of centre policies which will appeal to quite a lot of people.”

Britain’s electoral map means the Conservative Party needs to maintain a nine percentage point lead over Labour to win the next election.

One of Brown’s biggest policy headaches, at least in the early days, will be how to deal with the conflict in Iraq and the close ties Blair built with the US government under George W. Bush.

One option would be to back US Democrat calls for a faster troop reduction in the expectation they will take over the White House in 18 months. Brown has repeatedly said anti-Americanism is a mistake and is likely to disappoint those who feel Britain needs to stand up more to Bush.

Nicolas Sarkozy winning the French election and Angela Merkel leading Germany creates a greater consensus for reform with Europe but Brown, widely regarded as being cooler towards Brussels than Blair, may still face problems surrounding the EU’s constitution.

Blair is due to attend an EU summit at the end of June and looks likely to sign a deal on a treaty for the bloc. Too many changes could lead to calls for a referendum in Britain — something Brown will want to avoid at all costs.