BIRMINGHAM England (Reuters) - Eight months before a tight election, the three main contenders to succeed British Prime Minister David Cameron as leader of the Conservatives wooed potential supporters at the party's annual conference with starkly different pitches.
Cameron, 47, has repeatedly said he wants to lead his right-leaning party to victory in May 2015 and to secure a majority, so it can rule alone and not in a coalition as is now the case.
But the Conservatives trail the opposition Labour party in most opinion polls and the surging anti-EU UK Independence Party (UKIP) has poached two of his lawmakers in the last month. Capitalizing on disappointment among some Conservatives with Cameron's centrist policies, UKIP is likely to steal some of his voters too, making it harder for him to get re-elected.
Theresa May, the country's 57-year-old interior minister (home secretary), Boris Johnson, the 50-year-old mayor of London, and 43-year-old finance minister George Osborne have emerged as the main candidates to succeed Cameron if he loses.
All three contenders are Eurosceptics -- an important quality if they are to lead a party that is increasingly hostile to the European Union. All have professed loyalty to Cameron but none has ruled out a leadership bid either.
"This conference is to some extent a pre-audition for a leadership contest that might take place," Tim Bale, a professor at London's Queen Mary University, told Reuters.
"It's tricky for them (the contenders) to pull off. They have to lay out their credentials, while at the same time being seen as team players."
Even if Cameron wins the election but fails to get a majority there's a chance his party, which has a history of swiftly removing its leaders, could force him to step down anyway.
He mentioned all three politicians earlier in the day as potential successors, saying the party was lucky to have "a team of leaders".
May used her speech on Tuesday to offer an analysis of the dangers posed by Islamic State insurgents in the Middle East and Britain, promising she'd introduce sweeping powers to tackle extremism if her party wins next year's election.
"We must face down extremism in all its forms. We must stand up for our values. Because, in the end, as they have done before, those values, our British values, will win the day, and we will prevail," she said, before receiving a standing ovation.
Perceived to be on the right of a party that Cameron has pushed to the center ground, she also pledged to reintroduce a law, nicknamed the "snooper's charter", giving British police and security services some of the West's most far-reaching surveillance powers.
By contrast, Johnson used his speech to showcase his eccentric sense of humor, brandishing a brick to make a point about the need for more house building, talking up the achievements of London, the city he runs, and making a joke at Cameron's expense.
"You have permission to purr," he told delegates, a cheeky reference to a phone call Cameron had with Queen Elizabeth after this month's Scottish independence referendum. Cameron, to his embarrassment, was overheard saying the monarch had purred with happiness when he told her Scots had voted "No".
Johnson, who will seek election to parliament in a safe Conservative seat in May, quoted William Shakespeare's Henry V to issue a warning to any Conservatives considering defecting to UKIP.
"He which hath no stomach to this fight, let him depart”, said Johnson, whose speech drew sustained applause.
Osborne, sometimes criticized by left-wing tabloids as being tough on the poor, delivered his own speech on Monday, spelling out plans for more spending and welfare cuts in a calculated gamble that voters would understand and even welcome his tough approach to fixing the economy.
On Tuesday, he sat down on the sidelines of the conference for an informal "conversation" with activists in which he discussed everything from his efforts to control his weight to why he had decided to change his hair style.
The events offered a glimpse of the type of leaders May, Johnson and Osborne would be if they succeeded Cameron.
May, serious, more right-wing than Cameron, and tough on law and order, a cocktail likely to appeal to the party's core supporters. Johnson, jokey and more centrist than May, a mix polls show could widen the party's appeal and boost its support. Osborne, a fiscal enforcer with a flair for political strategy whose earnest style still turns off some supporters.
When asked about her leadership ambitions after her speech, May said Cameron was doing a wonderful job as prime minister, but refused to rule out running herself in future.
"I want to see David continuing as prime minister for many years to come because I think he has done a great job for this country," she told BBC radio.
When Johnson, who said during an interview that Cameron was leader "at the moment", was teased about his own ambitions, he accused the interviewer of trying to wind him up.
Osborne's close political alliance with Cameron and his perceived coldness -- something he and his team have worked hard to dispel -- are seen as complicating a possible leadership bid.
He too was non-committal when asked about such ambitions.
"This partnership I have working with David Cameron is one that I think is really strong for the country," he said.
"He's a great prime minister and he's going to be a great prime minister in the next parliament and long may that continue, long may I work for him."
Additional reporting by Guy Faulconbridge and William James; Editing by Dominic Evans