Today's front-page headline reads "Enough is enough, Mr Blair" and goes on to claim that Blair's second term is "dominated by spin and deception".
Inside the newspaper, although relegated to pages four, five, six and seven after a full-page story on Bruce Forsyth hosting a pro-celebrity ballroom dancing programme, the Express says Labour's policies on Europe, taxation, immigration, education, transport, health and pensions have triggered the switch.
The newspaper is owned by Richard Desmond, who made a £100,000 donation to the Labour Party prior to the 2001 election campaign. Last year Desmond denied that he offered a second £100,000 donation to the Labour Party, which was turned down after the party waded into controversy after accepting the earlier sum.
Before making the donation in 2001, Desmond had been a supporter of the Conservatives and there was widespread criticism that his switch of allegiance was suspiciously timed, coming as it did when Desmond was awaiting government approval for the takeover of Express Newspapers, which also owns tabloid the Daily Star.
In February there were reports that Desmond would cease supporting Labour if Gordon Brown took over from Tony Blair as prime minister, because Desmond "doesn't like Brown -- either as a person or his policies".
While the shift is undeniably a victory for the Tories, it is unlikely that the Express will have quite the vote-swinging impact of The Sun, which claimed that it pushed Labour to victory after it supported the party during the 1997 election campaign.
In the most recent Audit Bureau of Circulation figures, the Daily Express's circulation was down 2% to 942,171 -- less than half of its mid-market tabloid rival the Daily Mail, which has a circulation of 2,398,093.
The Daily Express had always been supportive of the Conservative Party under the leadership of Lord Stevens, but changed to Labour after it was taken over by Lord Hollick in 1996.
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