If Theresa May's sole goal for the Tory conference is to survive it, then she'll likely be less interested in what Boris Johnson was up to at his big ticket rally this afternoon, and more concerned about any comments made by the chairman of the 1922 Committee, Graham Brady. Brady is famously the man who keeps the letters calling for a vote of no confidence in the Prime Minister, and was introduced at a drinks event earlier in the conference as 'the man who knows where the bodies are buried'. He is effectively the general secretary of the Tory backbenchers' trade union, which makes him extraordinarily powerful.
Brady and his senior 1922 colleagues decided shortly after the snap election that it was more important for the country that the Prime Minister stuck around and offered some stability during the Brexit negotiations, rather than there being a protracted leadership contest. It was the 1922 Committee that called on ministers to stop misbehaving during that turbulent summer, and the 1922 Committee that has provided the stabilising influence during subsequent periods of tension. It is a measure of how weak May's personal authority really is that she has to rely on this Committee quite so much.
Today at a fringe event, Brady joked that his favourite number was a 'low one', a reference to the fact that he needs to receive 48 letters calling for a vote of no confidence in the Prime Minister for such a vote to go ahead. He also explained what his role was, saying 'I think I was elected chairman of the 1922 Committee as someone colleagues thought would stand up for them, but in a way which did not damage the Conservative party'. This is why he acts not just as someone who collects the letters, but also as someone who tries to call for calm when ministers are openly undermining the Prime Minister. He again pointed to the problems with ministerial indiscipline, complaining about the way discussions at Cabinet meetings tend to end up in the newspapers (generally via the James Forsyth app), and contrasting it with his own belief in discretion as Chairman.
It will come as a relief to May that Brady praised her resilience, telling the fringe that 'even the people who are not [fans of the Prime Minister] recognise somebody who is motivated by the right things, cares about the national interest, has a dogged determination and ability to absorb punishment that everyone admires'. This suggests that he and his senior 1922 colleagues still think it is best that May survives for a while longer, though there will come a point, possibly after March 2019, when Brady finds that his preference for low numbers may be superseded by the preference of the many leadership contenders for a vote of no confidence in the Prime Minister.