Latest data on campaign expenditure from the Electoral Commission has revealed that Labour raised twice as much as the Conservatives during the third week of the campaign.

Labour's supporters in the theatre, comedy, business and advertising, as well as the unions, boosted the party's funds by £650,000 compared with the Tories’ third week total of £326,000.

The Liberal Democrats raised £25,000 through a single donation while the UK Independence Party received £31,000 for leaflet printing and polling.

The donation of £250,000 from Amicus to Labour follows a gift of £273,000 from the T&G in the first week.

Celebrity donors to Labour included Sir Christopher Ondaatje, the publishing millionaire and regular donor, who gave £100,000; Sir Gerry Robinson, chairman of Allied Domecq, who gave £15,000 and Eddie Izzard; the comedian, who gave £10,000.

The Times reports that Michael Spencer, the chief executive of Icap, the world’s biggest inter-dealer broker, has given £300,000 to the Tories since January.

These funds are believed to have bankrolled the £250,000-plus costs of Lynton Crosby, the Australian polling guru, who is masterminding the Tory election campaign.