David Cameron saved his best until the last PMQs of this Parliament. Perhaps it was having his wife, Samantha, and two of their children watching from the gallery, or perhaps he was just demob happy. But for whatever reason, he combined professionalism with throwaway wit of a most happy kind. Not for nothing could his daughter, Nancy, be seen clapping and heard shouting “Yeah!”.

There were moments when Cameron got things wrong. He made a minor but potentially humiliating slip when he said that Michael Connarty (Lab, Linlithgow and East Falkirk) is standing down at the election. Connarty hopes to carry on. Cameron had to say “Let me rephrase that”, and an embarrassing stutter could have followed. But instead he used the occasion to observe that this was his 146th PMQs, to pay tribute to his “team” – a wave at the bench to the right of the Speaker’s chair where they sit – and to say that they almost always get things right, after which he paid tribute to Connarty too, and wished him luck.

No Scottish Labour MP is likely to thank Cameron for his support against the SNP. But the Prime Minister had won credit for standing up for his staff while at the same time blaming them for his mistake: a considerable achievement.

The ingenious and witty Stephen Pound (Lab, Ealing North) asked a short, clever question, in which he suggested it was time to stop calling Cameron “chicken” and start referring to him as “a lame duck”. Cameron came back with: “I’ll tell him what is a lame duck and that is trying to get into Downing Street on the back of Alex Salmond’s coat tails”. He capped this with: “Never mind ducks, I’m looking at Alex Salmond’s poodle.”

Cries of “woof, woof” from the Tory benches, directed at Ed Miliband. They loved this, while the Labour benches looked on in despair. For their man had already made an idiot of himself. He demanded a straight answer: would the Prime Minister rule out raising VAT?

Cameron astonished him by answering: “Yes.” Miliband could not come back from that. He and his team should have seen it coming, but they are useless, and now they had exposed themselves as useless. The Prime Minister followed up his advantage: would Miliband rule out an increase in National Insurance contributions? Miliband refused to say. He was not, of course, under any obligation to answer Cameron’s question, but for Labour the contrast between their man and the Prime Minister was horrible. The Conservatives will now hammer away at “Labour’s jobs tax”. Labour MPs know there is a risk, as in 1992, of voters refusing to back their party because it will raise taxes and has a leader who doesn’t look like a Prime Minister.

Simon Danczuk (Lab, Rochdale) asked a question about the entirely disproportionate number of people – 680 of them – seeking asylum in Rochdale. It was a good question, but this was not the week to ask it. For Cameron said the legislation which gave Rochdale so many asylum seekers had been passed by Labour, and then quoted with relish some incredibly rude things Danczuk has said in the last few days about Miliband, or has reported the voters saying. What a humiliation for the Labour leader: to command so little loyalty on his own benches, and to have such an inefficient whipping operation, that Danczuk was allowed anywhere near this week’s PMQs.

Cameron raised Tory morale by his performance, which was perhaps his best ever at PMQs, or at least his best ever at an important moment. He showed his own backbenchers that they have a good story to tell, he demonstrated his relish for telling it, and he exposed Miliband’s grievous weaknesses. Many of us have feared this election will be very dull, with Cameron behaving like a Lynton-Crosby-controlled robot. Cameron demonstrated that he is not going to try to wear us down like that. He will dare to be himself.

The party which fights the most amusing and professional campaign does not always win the election. But Labour MPs now know, with horrible clarity, that they are going in to battle under the command of a man who acts like a poodle.