Ian Burrell: Newspapers have made up their minds already

We're only two days into the election campaign and already most of the papers seem to have forgotten their differences with the leaders of the parties which traditionally count on them for support.

The Daily Mail, having undergone a long and awkward courtship with David Cameron, showed its support in the way it knows best yesterday by playing the immigration card, criticising the influx of foreigners into the job market with "Labour's Betrayal of British Workers".

The Daily Telegraph, where traditionalist columnists such as Simon Heffer have been among the most vociferous critics of Cameron's suitability as a Tory leader, has also rallied to his flag. The Telegraph won plaudits for its coverage of the expenses abuses of politicians of all hues but it becomes more partisan when an election is in the offing. "Brown 'at war with bosses'" was yesterday's front-page splash description of the Prime Minister's relationship with business.

In the red corner, The Guardian – which has been critical of the Prime Minister and even momentarily fluttered its eyelashes at Cameron – opened up on Wednesday with a front-page picture of Gordon Brown with his Cabinet and beneath the adoring headline: "Personal, proud, defiant: Brown takes his case to the country." Yesterday it followed up with a splash that claimed to expose conflicts of interest in Tory plans to cut NHS spending.

The Independent never aligns itself to any one party and marked the start of the campaign with a picture of Gordon Brown and the neutral headline: "A Step into the Political Unknown". Most interesting is the position of The Times, historically a Tory paper but with recent ties to New Labour. Its front page response to the calling of the election "The battle for Middle England" was non-committal, and rather overshadowed by a large picture of the footballer Lionel Messi. Yesterday it was far from supportive of the Tory leader in "The Cameron Question", asking "The best thing since sliced bread? Not everyone is convinced..."

Other sections of Fleet Street were nothing if not entirely predictable. The "Last Chance to Save Britain" front page in the Daily Express yesterday felt like a tired echo of the Neil Kinnock bashing of The Sun in a previous era. The Currant Bun itself, at Cameron's side since the Tory party conference, followed Wednesday's opening gambit of "D-Dave" with a crude slug at the Prime Minister's plans to raise National Insurance "Brown's a Clown". The Daily Mirror greeted news of the election date with front page pictures of Cameron and shadow Chancellor George Osborne and the headline "Don't Get Conned".

This campaign may be the closest we've come in modern times to a three-way election battle – with the real prospect of a hung parliament and the LibDems holding the balance of power – but Fleet Street is treating the campaign largely as a traditional two-horse race.