European bookmakers have cut the odds on Sarah Palin being dumped as John McCain's running-mate after the revelation that her 17-year-old unmarried daughter is pregnant.

Mr McCain's decision to name the Alaska governor as his wildcard pick has infused his campaign with a jolt of youthfulness and enthusiasm - as well as millions of dollars in donations.

But the London bookmaker William Hill says that there has been "no great rush" to back the Arizona Senator since Ms Palin was chosen. Indeed, the firm has cut its odds on her not being still on the ticket come the election from 20/1 to 8/1.

"It would be disastrous for his campaign were McCain to sack Palin, but it is not impossible that she could stand down should party chiefs feel that she is too controversial a choice who might end up costing McCain votes, rather than boosting his campaign," said spokesman Graham Sharpe.

William Hill currently offers 13/8 that John McCain will become President, with Barack Obama quoted as 4/9 favourite, meaning that a punter who best £9 on an Obama victory stands to win £4 if he makes it to the White House.

Meanwhile, Ireland's largest bookmaker, Paddy Power, reported a “steady flow” of support for Mr Obama - and uncertainty around Mrs Palin.

Paddy Power are also offering odds on what surprise the Alaskan governor will spring next on American voters, including, at 40/1, a possible addiction to moose burgers.

Best odds:

Barack Obama to win: 1/2

John McCain to win: 7/4

Sarah Palin to be caught breaking and entering an igloo: 250/1

Times Recommends

• Rio Tinto four held as China prepares case
• Diplomats must keep heads down and trousers up
• When in Rome should one make like Berlusconi?