TORIES in a key Merseyside seat are refusing to say if they received up to £90,000 from controversial "non-dom" donor Lord Ashcroft.

The Wirral West Conservative Association clammed up over the origins of huge sums described as its “fighting fund” in accounts filed with the Electoral Commission.

Almost £60,000 was received in 2005 alone – the year of the last General Election, when the seat was almost snatched from Labour – more than doubling the association's war-chest to £95,168.

Furthermore, after that election, Lord Ashcroft funded research in Wirral West and 11 other key constituencies to find out why voters were turning their backs on the Tories.

In other marginal seats – Labour won Wirral West by just 1,097 votes five years ago – the “fighting fund” has come from Conservative central office, much of it bankrolled by the billionaire peer.

Tory leader David Cameron has now been plunged into a damaging political row by Lord Ashcroft's admission that, contrary to promises given when he became a peer, he pays no tax on his huge overseas earnings.

The Wirral West accounts reveal that a total of £85,291 was received under the heading “fighting fund” between 2005 and 2008, including £59,873 in 2005 and £17,924 in 2007.

A further £8,325 was attributed to “Central Office grants” – making a total of £93,616. There are no filed accounts for 2009, leaving open the question of whether spending has been ramped up ahead of this year's election.