In fact, he claims that The Sun switch lost the paper 204,000 sales, month on month, in April. Certainly The Mirror had a good election; its pro-Labour tub-thumping had the ring of confidence - it felt as if the paper meant what it said and hero-grams from the chief executive were pasted on every available notice board in the building the morning after the result. The Sun, a recent convert to New Labour, was without its usual gung ho, eye-jabbing gut commitment.
But all that was just a phoney war. Within 10 days of Blair's coronation, real mayhem had erupted. In what The Mirror modestly called "a sensational transfer coup", it "bought" the nearest thing to Mystic Meg herself - their custom-made, it-could-only-be-him reporter, Lenny Lottery.
On Saturday 10 May, under the headline "Lottcha! Lenny one else is a fake!", we learnt that Lenny had left the "sinking Sun" to write for "Britain's Number One newspaper". "Now I know what it feels like to win the jackpot. It's a dream come true," he said.
The Sun hit back with the immediate appointment of a new lottery reporter - to be known as Sir Lenny. "New Labour, New Lenny," boasted the headline. "A new Big L for the Mil-Lenny-ium."
The Lenny Lottery story began with the launch of the National Lottery two years ago. Both The Sun and The Mirror realised the huge potential for stories: winners, losers, rats, divorcees, sex addicts, jail birds and profligates.
The Sun stole a march by persuading (ie instructing) a hapless member of the newsroom, one Aidan McGurran, to change his name by deed poll to Lenny Lottery. His brief: to make sure the paper does not miss out on stories about winners, losers, rats, etc...
As the initial excitement of the Lottery wore off and we got used to the idea of millionaires being created at the drop of a tombola ball, the story count dropped and Lenny began to fade into merciful obscurity. And so it remained until Piers Morgan told his morning conference to stand by for his important announcement.
According to Mirror sources, The Sun and its editor Stuart Higgins were initially discombobulated by Lenny's departure (or gobsmacked as we say in the trade). Not so much by his going - "Frankly," said a senior executive, "Aidan had been selected only because he wasn't that great shakes as a reporter. The best stories came to us because we had made it our business at a senior level to get to know Camelot, the lottery organisers." No, what really miffed them was that Lenny had left taking his name and his lottery suit - a dashing little number in white covered in red numbered balls - with him.
A Mirror source said: "Apparently Higgins didn't fight very hard to keep him. He offered him a little more money and wished him well. It was only when he was out of the building that The Sun realised they had not made sure they had copyright on the name and hadn't stopped him walking out with the suit."
Frantic calls on the mobile ensued, but Lenny was on his way to the "best paper in the country". "There was a fantastic excitement in the building," says a somewhat unexcited journalist. "We were told he was on his way by limo, or jet-ski up the Thames from Wapping, and then he turned up looking absolutely terrified."
Battle was joined. By Wednesday, The Sun's replacement reporter had the splash: "Lotty's Gotty Hubby's Potto" - a story of a "pretty blonde", Lotty Abrahams, who won pounds 250,000 in a syndicate and decided to keep her husband's pounds 250,000.
The poor bloke had been paying in his pounds 1 a week but she had ditched him because of his gambling (sic) and felt she deserved the loot (See winners, losers, rats ... above).
The Mirror riposted with the news that the disgruntled hubby was going to sue and also broke the news that a High Court judge had ruled Lenny could keep the suit he had taken from The Sun. But only for one day. The Sun hit back with the appointment of Lady Lottery, a healthy-looking young brunette, "Sir Lenny's bosom pal".
On Friday The Mirror had "Help our Lenny win the Lawtery" - an appeal to the readership to help Lenny in his High Court action keep the the suit safe from The Sun.
But it was not to be. That afternoon Mr Justice Neuberger brought what The Sun called "the full majesty of the law" to bear on the issue and pronounced that the suit must be returned . "Who wears wins" was the small headline at the top of Saturday's Sun front. Was The Mirror cast down? Give us a break!
It devoted its whole front page to a victory celebration. A verdict may have been handed down on on the red-balls -on- white- background garment (`Lenny's tatty old gear' The Mirror called it) but Mr Justice Neuberger had only opened the way for the white-balls-on-red background affair, "his dazzling new dreamcoat."
So now everyone is well suited. But that apart, where do things stand now in this gripping tale? As far as lottery exclusives go, The Sun is ahead with the story of Lotty Abrahams. The Mirror made do with the Lenny Lottery life story: he supports Everton, grew up in a council house, was bullied at school, and wanted to be a politician (Labour).
But can all this win circulation wars?
"We find Sun readers love to read about people like themselves who become millionaires," an executive revealed to me exclusively. "Particularly when they are in syndicates. Because many of the readers are in the C, D category they are happy to talk to us. They like to share their good times, and bad times. The readers feel it really `could be them'."
Furthermore, The Mirror has to overcome a certain coolness from Camelot after a succession of attacks on their fat-cattery. Camelot refused to be drawn on that, although the company seems more comfortable with The Sun. Spokesperson Joanna Manning-Cooper said: "We want to stay out of it. We wish them both well, though it does get confusing with two Lennies phoning."
Will Lenny's arrival help The Mirror circulation? At the week ending 19 April, the gap between the two papers was 1,455,000. On 10 May, it was 1,454,000. The nearest The Mirror got to its rival was 1,373,000 behind. It is too early for the Lenny effect to kick in.
One would like to agree with Piers Morgan that The Mirror's upward move was the result of the journalism during the election. Clearly it was good for the readers and paper to be on the winning side and there was a lot of old-fashioned commitment to the cause, notably a long "Why I'll vote Labour" piece by their best home-grown columnist, Brian Reade. As one senior Mirror man said, the election coverage reminded him of the paper of the Seventies. On the other hand, some of the increase in sales might have something to do with a TV campaign for cut-price flights.
So maybe the paper does have the secret for the way ahead: New Labour, New Lenny ... and more cheap deals.