Isabel Hardman

Tory MPs might have appeared keen to support the PM after his surprise EU bill when they spoke in the Commons this afternoon. But behind the scenes the party is in a pretty precarious situation. Open unrest is being held back by two things: a realisation among backbenchers that they do need to hunker down as a by-election approaches and the General Election draws nearer, and the Prime Minister's pledge that 'we are not paying a sum anything like that'. But neither is guaranteed to keep critics quiet forever. Backbenchers point out that the current party loyalty at the moment is motivated by a desire to beat Labour - and a belief that the Conservatives really can do that.

Kelly Tolhurst has won the open primary to be Conservative candidate for Rochester and Strood, I understand. The result is not due to be announced until this evening, but I hear that Tolhurst won by fewer than 50 votes on a turnout of 4,000. The turnout is the key in this as it will give some indication as to the level of interest in the constituency in the Conservative candidate. It is worth bearing in mind that the turnout in Sarah Wollaston's open primary in Totnes was 16,497. That much lower turnout in a more high-profile contest following a defection will add to party worries following yet another poll showing Ukip ahead in the constituency. UPDATE, 20.10: Tolhurst has been confirmed as the candidate.

One of the bits of their Parliamentary party meeting this week that cheered Conservative MPs the most was a speech by Tracey Crouch on why the Tories could win the Rochester and Strood by-election. Many of her colleagues who like to spend their spare time staring at spreadsheets are sincerely worried that the party could lose the seat, leading to all hell breaking loose in the party. Crouch, who represents the neighbouring constituency and will act as the campaign aide to the candidate once she is selected (the shortlist in the postal primary is a choice between two women), told the room that the demographic of Rochester favours the Conservatives far more than that in Clacton: it has fewer pensioners, more professionals and the voters are on higher incomes.

Is Number 10 really preparing for a U-turn on the European Arrest Warrant? After Coffee House reported some odd manoeuvres by chief whip Michael Gove involving him suggesting to Tory MPs that it might be better for the government not to opt back into the EAW, the topic came up at this afternoon's lobby briefing. The Number 10 spokesperson told journalists that: 'The government has set out the areas where it is, in principle, seeking to opt back in. We want to secure European agreement on that and then we will take a final view on which ones we opt back into.' That sounds rather like there is room for a shift. But a Number 10 source is insisting to me that 'there is no change'.

Whatever David Cameron's promised 'big bang' announcement on immigration in the EU is, it has certainly excited Conservative backbenchers. A group of them confronted him this afternoon to ask whether Britain would be moving to a points-based system for EU migration along the lines of Australia (something Ukip advocates), and they say that he did not reject it. This has made them even more excited. The Prime Minister was speaking to the 'No Turning Back' group of Tory MPs, which some of those present at the meeting described as 'a little uncomfortable', mainly because these are the MPs who tend to cause him the most trouble. Others felt the meeting was relaxed, but left wondering whether Cameron really would deliver on these hints that he's been dropping over the last few months.

The Tories will announce a big new policy on freedom of movement in the European Union, David Cameron told his MPs tonight. At a meeting of the Parliamentary party, the Tory leader promised what one Eurosceptic attendee described as a 'big bang' announcement on freedom of movement. Apparently this pleased those there no end, even those usually critical of the Prime Minister. MPs were also told they are expected to visit Rochester to campaign at least three times, and the cabinet five times, which is clearly an intervention from Lynton Crosby as the whips had decided at the end of last week that they wouldn't bother. This was what one source close to the PM described as 'a call to arms for us all'.

The Tories may have watched Douglas Carswell's re-entry into the House of Commons in silence, but he seems to be getting a reasonably warm reception from his old colleagues behind the scenes. He has already exchanged jokes and arranged to dine and drink with a number of them. For a few weeks this will send the whips into a spin, as they try to work out whether it really is just lunch, or a brewing defection. But it wasn't just Carswell who was nattering with Conservatives this afternoon. Nigel Farage, who watched his first elected MP re-join the Commons from a gallery, has also been talking to some of them. Philip Davies was spotted shaking Farage's hand in the members' lobby, while others tried to press the Ukip leader on the possibility that the Right may one day unite.