With ballot papers due to go out tomorrow to the party’s 8500 members, a senior activist came forward with new allegations about Ramsay Jones, the party’s director of media, who has been suspended.
Davidson also suffered a blow to her credibility when it emerged she had failed to win the support of a single party chairman in her Glasgow seat.
Jones, 51, was suspended from his duties on Wednesday after the Sunday Herald revealed last week that he attended a meeting of campaign strategists at Davidson’s home, despite being ordered by the party chairman not to take sides and remain impartial.
Jones appeared days after supporters of a rival candidate, Murdo Fraser, complained about his behaviour to chairman Andrew Fulton.
Davidson’s team knew concerns had been raised over Jones’s neutrality, yet he was welcomed into the candidate’s Glasgow flat on September 18 regardless.
Her camp insists there was nothing untoward about a visit that would involve Jones making a 150-mile round trip from his house in Dunbar, East Lothian, on a Sunday during the campaign.
However, Malcolm Macaskill, a former Holyrood candidate, has claimed Jones previously boasted he was a “big fan” of Davidson and recruited her to the party about three years ago.
Macaskill said Jones lavished praise on Davidson when the pair talked in the garden lobby at the Scottish Parliament in February.
Jones will remain suspended until at least the end of the race to replace Annabel Golide, on November 4, and could face disciplinary action.
Macaskill told the Sunday Herald: “I was disappointed to hear Ramsay may have been supporting Ruth Davidson’s campaign for leader. That would be wholly unprofessional.
“But it was no surprise, as Ramsay stated to me he was a big fan of Ruth and he had been responsible for bringing her into the party.”
At the time, Macaskill was the Tories’ No 1 candidate on the Glasgow list for Holyrood. A few weeks later he was dumped by the party hierarchy in a row about his financial history. His exit meant Davidson, who was running Goldie’s Holyrood office, moved to the top of the list.
Without the switch, Davidson would not have been elected as a list MSP for Glasgow in May.
Although the least experienced of the four candidates for the leadership, the 32-year-old has emerged as the favourite of the Tory establishment, with backing from Thatcher-era grandees Lord Forsyth and Lord Sanderson, and the sole Scots Tory MP, David Mundell.
However, her campaign has been plagued by gaffes and rumours that she has received unofficial help from the Conservative Party hierarchy.
She was recently forced to sack her parliamentary assistant Ross McFarlane after he was caught on camera drunkenly burning a European Union flag in a Glasgow Street as a companion made sectarian remarks.
Macaskill said that by allowing Jones to attend a sensitive strategy meeting at her home, Davidson had blundered.
He said: “Once again, Ruth’s judgment is called into question. Having previously run the leader’s office, she would be well aware of Ramsay’s necessity to be seen to be neutral.”
The Sunday Herald has also established Davidson is facing hostility from party activists in what should be safe home turf in Glasgow.
The four leadership candidates will take part in a hustings in the city tomorrow.
Of the city’s five constituency association chairmen and women, two are supporting Davidson’s main rival, Murdo Fraser, two are behind Jackson Carlaw, and one has nominated Margaret Mitchell.
Supporting Fraser are Richard Sullivan, chairman of Glasgow Central & Eastern, and Archie McIntyre, of Glasgow South West association.
Barbara McCulloch, in Glasgow North West, and John Anderson, in Glasgow North, back Carlaw.
In Glasgow South, Alastair Mackenzie signed Mitchell’s nomination papers, though it is understood he will vote for Fraser.
In contrast, Fraser is backed by three in his Mid-Scotland and Fife region, while Carlaw is backed by two in West of Scotland.
Sullivan said: “Ruth’s support does appear to be lacking in Glasgow.”
A spokesman for Davidson said: “It is not true to say Ramsay Jones recruited Ruth to the Conservative Party because she was already a member of the UK party. It is a fact Mr Jones – a friend of long standing – encouraged Ruth to contest the Glasgow North East by-election.”
Asked how Davidson was supposed to win over voters if she could not persuade activists in her home patch, the spokesman said: “She’s doing it by meeting grassroots members on the nationwide tour. What polls there are put her in front. The feedback is very positive.”
Jones declined to comment.