Unrest over the government's controversial Health and Social Care Bill is growing as calls to stop its passage "before it is too late" have now come from behind Conservative lines, on fears it could cost the party the next election.

Tory blog ConservativeHome claims it has been contacted by three Tory MPs who have "rung alarm bells" about the proposed National Health Service reforms, with one calling for the bill to be axed, another for Andrew Lansley's head, and the other drawing comparisons with the ill-fated poll tax of the 90s.

According to Tim Montgomerie, Editor of ConservativeHome, "the consensus is that the Prime Minister needs an external shock to wake him to the scale of the problem", and he argues that every inevitable problem that arises in the NHS in future will be blamed on a bill that is "not only mangled and bureaucratic, but also unnecessary".

Last week, the bill - which seeks to hand over a huge chunk of money to commissioning GPs and boost private sector involvement in the NHS - was reintroduced to Parliament following fierce opposition last year. But the government has been smacked by defeat again when Peers in the House of Lords voted 244 to 240 in support of an amendment to give mental health a more equal footing with physical health. 

Debate on further amendments to the bill continues this week, but there remains a significant shadow of pessimism over its future. Speaking to the BBC1's Andrew Marr show, shadow health secretary Andy Burnham said he believed the bill would not be passed, and slammed the government for combining "the biggest financial challenge in the history of the NHS with the biggest ever reorganisation".

Pressure mounting

Labour leader Ed Miliband has condemned the health plans as a "complete disaster", while in a letter to the Guardian the British Medical Association, Royal College of Midwives, Royal College of Nursing and the Chartered Society of Physiotherapy called on Peers to vote against the bill, arguing that it is an "unnecessary distraction when the NHS should be focusing on a far more important issue: finding the £20bn in efficiency savings it needs to make at a time when demand is increasing".

And it is not just the Bill's future that is in question, with Lansley's role in health also looking a little shakey, despite support from coalition leaders. Conservative backbencher Nadine Dorries wrote in the Mail on Sunday: "It is clear that Cameron wants to kill his own NHS bill - and Lansley's career with it." 

ConservativeHome's Montgomerie says Lansley "will have to move on", and senior Liberal Democrat Simon Hughes told the Marr show that "in the second half of parliament it would be better to move on from battles over the bill", so Lansley should change roles once the health reforms are in place.