Set against this was a promise to put everything that comes from Europe from now on through a new sovereignty act that would require a referendum on any further ceding of powers to Europe. Cameron apparently received loud applause when he told his MPs that never again would a treaty pass into law without a vote.
It looks for now like this will be enough to keep most of the party on side. There will, though, be disgruntlement that there is no new referendum pledge. Several Euro-sceptic shadow Cabinet members that I had spoken to before today thought that it was important that the results of any renegotiation be put to a vote.