Labour leader Ed Miliband said today the party's fightback to power had begun.
Mr Miliband insisted that with him at the helm the Labour Party would be true to its ideals.
He also used his speech to the Scottish Labour conference in Oban to launch a fierce attack on the Conservatives, whose programme of spending cuts he branded as "economically wrong" and "grossly incompetent".
Mr Miliband used much of his conference address to set out the differences between his party and David Cameron's Tories, portraying Labour as optimists with a "different view of society" from the Conservatives with their "pessimistic idea" for a "big society".
Labour, he said, believed in "acting together so we can change the world".
But he said that the "forces of pessimism tell us that a belief that our world can change is a flight of fancy".
And he added: "I'm afraid that is today's Conservative Party. That is David Cameron."
The Labour leader insisted his party was ready to "take on the pessimists".
He said: "There is no role for this party as one of protest - we must be a party of government again."
With Holyrood elections just six months away, Mr Miliband said that vote would be "a vital moment in Labour's rebuilding across the United Kingdom".
He said Britain could not afford for the Conservative-Liberal Democrat Government to be "anything other than a one-term coalition".
He told party activists: "We are ready to take on the pessimists. There is an alternative.
"Labour's fightback has begun. We are ready for the fight. Let's fight for the people we came into politics to serve."Reuse content