Mr Cameron has suffered a series of rifts with a sizeable portion of his backbenchers over Europe, gay marriage and Lords reform.
BBC: John Hayes
2.
Both David Cameron and Nick Clegg know that for all the talk of House of Lords reform or gay marriage, the reality of their problem is that the economy is not shifting and they've got to get it to move.
BBC: Side-by-side, but looking apart?
3.
Critics who dismiss reform of the House of Lords or legislation for gay marriage as unpopular irrelevances have just been given fresh electoral ammunition.