Trouble for Cameron - from the Conservatives

David Cameron returns from paternity leave on the day after his deputy, Nick Clegg, successfully steered the Alternative Vote Referendum Bill through the Commons. But Cameron's troubles when it comes to constitutional reform aren't going to go away, and despite some vocal Labour opposition to yesterday's Bill (despite Gordon Brown having promised a similar referendum in his dying days as PM), it is from the Conservative benches that Cameron is going to face his most serious opposition.

Tory whips had to do some pretty severe arm twisting to bring recalcitrant backbenchers into line last night, but the Conservative parliamentary party has no shortage of hard-liners who detest the coalition, and see the constitutional reform proposals as little short of a Lib Dem legislative coup. Not only is a head of steam building behind various wrecking amendments to the Bill, but it is clear from various Tory contributions to yesterday's debate (as reported by the AV sceptical Conservative Home site) that bringing his own party into line could be a more difficult task for David Cameron than he imagined. He may wish he'd extended his paternity leave a bit longer.