By Nick Assinder
Political correspondent, BBC News website
Gordon Brown probably cannot believe his luck. Barely more than a month in office and already there are signs of real panic in Tory ranks.
Mr Cameron says he will not change direction
David Cameron, on the other hand, probably cannot believe just how easily some of his big backers have apparently lost their nerve at the first whiff of cordite.
Exactly a week ago one of Mr Cameron's regular critics, Lord Kalms, warned him he faced a "summer of discontent" unless he changed tack.
Sure enough, in what has signs of a coordinated campaign, there has now been a flurry of attacks all with a single message - that Mr Cameron has failed to offer distinctive, serious and appealing policies, preferring spin and PR.
There was an irony in the fact these latest assaults came on the very day Mr Cameron was trying to provide some substance with a fresh policy on schools discipline which was entirely overshadowed by the attacks.
That will have been frustrating enough for the Tory leader, but what will worry him most is the fact that the recently-acquired Tory discipline seems to be breaking down.
His recent setbacks over grammar schools and in a brace of by-elections, combined with the "Brown bounce" and the bad timing of his trip to Rwanda while his constituency was flooded have hit his poll ratings.
Mr Cameron's Rwanda trip coincided with bad flooding in England
But he may have been taken aback at the readiness, even apparent willingness some of his own side have shown in using those events to attack him.
The big danger is that such assaults suggest to voters that the Tories have not changed and are still pressing for a return to older policies - particularly on issues like immigration, Europe and taxation, all of which Mr Cameron believes harmed them in previous elections - and are as ready as ever to turn on its leader.
It may be relatively easy for Mr Cameron to dismiss Lord Kalms as a constant critic and supporter of failed leadership contender David Davis (in other words one of the group formerly known as traditionalists).
And he has lost little time in slapping down Ali Miraj for launching his criticisms only the day after apparently asking to be made a lord.
The sniping from former frontbencher Graham Brady and ex-party chairman Lord Saatchi may appear more weighty, but even they still echo the traditionalists' demands for a return to previous and, as far as Mr Cameron is concerned, failed policies.
And that is precisely what Gordon Brown seems to be plotting by attempting to fence off the centre ground for himself and leaving nowhere else for the Tories to move but to the right.
The demands for substance are beginning to be answered with big pieces of work on, for example, social breakdown and security and, as Mr Cameron has pointed out, there will be more over coming weeks.
Whether the substance will be of the sort demanded by the critics, however, seems highly unlikely.
So, at the end of the day all this leaves one question hanging in the air. And it is one his detractors have not answered, at least not as far as anyone can tell.
If Mr Cameron refuses to cave in to their demands, and he shows absolutely no sign of doing so at the moment, what then?
Do they carry on sniping right through to the next general election with the danger of leaving their leader damaged and beleaguered at that poll, do they retire hurt or do they attempt a coup?
And if it is the last, who do they believe should replace Mr Cameron - or would even want to put their heads over the parapet at this point - and just how would they bring that change about, through a lengthy leadership election or by political assassination?
As for Mr Brown, if he perceives a disunited, uncoordinated and only half-reformed Conservative Party facing him he might well think that autumn general election isn't such a bad idea after all.