FACTBOX-Highs and lows of Gordon Brown's premiership

(Reuters) - Prime Minister Gordon Brown faced his first major electoral test on Thursday as Britons voted in council elections in England and Wales and for London mayor.

Brown overturned a deficit in his Labour Party's poll ratings after succeeding Tony Blair on June 27, 2007, but his strong lead over the Conservative Party has since crumbled.

Following are some of the highs and lows of Brown's leadership of the Labour Party.

June 29-30, 2007 - London and Glasgow are targeted in attempted car bomb attacks, only days into Brown's premiership. Brown receives praise for a measured, firm response.

Mid-June to early July - Britain hit by worst floods in 60 years. Brown wins approval for his government's handling of the crisis.

Aug 4 - Brown cuts short vacation to oversee response to an outbreak of foot and mouth disease in cattle. Brown's government is praised for swift action.

Aug 12 - A poll gives Labour its biggest lead over the Conservatives since before 2003 Iraq war. YouGov puts Labour on 42 percent versus 32 percent for Conservatives. The lead fans speculation Brown will call an early election.

Sept - Brown and his aides allow speculation to run that the prime minister could call an election as soon as October, but storm clouds begin to gather. Trade unions vent anger over a squeeze on public sector pay rises and homeowners worry about the impact of higher interest rates on house prices.

Sept 14 - Bank of England rescues Northern Rock as the mortgage lender becomes a casualty of global credit crunch, with people forming long queues outside its branches to withdraw their savings.