Joanna Cherry has insisted Ash Regan is "making progress" to becoming the next SNP leader despite her campaign struggling to win support.
The SNP MP is the only high-profile party member to have publicly endorsed the former community safety minister's bid to replace Nicola Sturgeon.
Cherry said today: "I think it’s very wrong to write her off, she’s making progress and I’ve heard a number of people say they’ve been switched on to her campaign after listening to her properly at the hustings."
Regan was mocked last week after suggesting a "readiness thermometer" could help deliver Scottish independence.
Speaking at an SNP hustings alongside leadership rivals Humza Yousaf and Kate Forbes, she said the device could be erected in Glasgow and Edinburgh and would have "a dial on it that moves" showing the nation was fully prepared to leave the UK.
Alex Cole-Hamilton, the Scottish Lib Dem leader, called the plan "weapons grade bananas".
Cherry also claimed that Regan showed "great courage and leadership" when she resigned in opposition to the Scottish Government’s gender recognition reforms.
She said the sudden nature of Sturgeon’s departure meant all the leadership campaigns had to be launched quickly with little preparation and no time to develop a policy platform.
Cherry said: "It’s no secret that the party machine is behind Humza and not behind Kate and Ash."
When it was put to her that the "party machine" would deny this is the case, Cherry said: "The majority of parliamentarians who have declared are behind Humza.
"We’ve already had a couple of cases of people wrongfully using the party’s internal mailing system to support Humza."
It comes as MSP Emma Harper had been sanctioned for using an internal email system to encourage members to vote for Yousaf.
MP Kirsten Oswald, the SNP’s business convener, told the Times: "The HQ team takes great professional pride in their impartiality.
"All are working diligently and are ready to give the full weight of their support and expertise to the new party leader, whoever that might be."
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