Brian Paddick has beaten former MP Lembit Opik in the vote to be the Liberal Democrats' candidate in next year's London mayoral election.
Four people stood for the party's nomination with Mr Opik finishing last.
He said: "I think like every great politician you have to have some wilderness years. Nelson Mandela had them. Many other people had them."
Former Metropolitan Police officer Mr Paddick came third in the last mayoral election in 2008.
Mr Paddick was elected by a narrow margin, with 1,526 votes to London Assembly member Mike Tuffrey's 1,476 in the second and final round.
Former Haringey councillor Brian Haley also appeared on the final shortlist.
Mr Opik came last in the contest, securing 252 votes in the first round.
Lembit in the wilderness, eh ?
If only .....