The Ottawa lawyer insists he's still a candidate and will remain so until the votes are counted on April 14.
But his campaign manager, Kevin Chalmers, has left and is now working on Vancouver MP Joyce Murray's leadership campaign.
Chalmers said Bertschi's financial agent has also quit and confirmed that money woes are plaguing the campaign.
"I certainly left under very good terms with David and I wish him the best," Chalmers said in an interview Friday.
"It is my belief that, while he will make whatever decision that he feels is best for himself and his campaign, I don't believe that spending the money that I would cost in using my talents would be worthwhile if the conclusion he comes to is the one that I suspect he will."
There have been rumours for weeks that Bertschi exceeded the $75,000 loan limit set by the party almost immediately upon launching his campaign last November.
"As with all and any campaigns, as you well know, there are certain caps and limits and whatnot and you have to go out and fundraise and you have to maintain a campaign that works within those limits," Chalmers said.
"And at some point, I think one has to question whether, given all the rules that one has to abide by ... it comes to a point where you just simply say, 'Look, there's no more I can do.'"
Questions were raised about the financing of Bertschi's leadership bid after he filed his first financial report with Elections Canada in early January.
In that report, Bertschi indicated that he'd personally loaned his campaign $75,000 and had also donated $10,000 — well above the legal maximum of $2,400 that a candidate can donate to his or her own campaign.
His wife also donated $2,500 — $1,300 more than the legal maximum for an individual.
Bertschi said Friday that those donations were really loans — suggesting he exceeded the party's $75,000 loan limit from the outset.
The party has also set a limit of $25,000 on the unpaid expenses a candidate can accumulate.
Exceeding either limit could result in sanctions from the party, including being kicked out of the race. Insiders expect Bertschi to voluntarily withdraw before that happens.
However, Bertschi insisted the "over-contributions" will be repaid by March 23, when candidates must file updated financial reports with Elections Canada.
"It's just an over-contribution, which is no big deal," he said in an interview. "So there's no problem there at all."
As for his financial agent quitting, Bertschi said she was a volunteer who became overwhelmed by the work. The job has now been handed over to someone with more accounting experience, he added.
Leo Bourdon, who had been on a "brief sabbatical" as Bertschi's deputy campaign manager, has taken over from Chalmers as campaign manager.
"We're actually stronger and better, in my humble opinion," Bertschi said.
"I'm looking forward to finishing this race strong ... It's a challenge but I'm up for it."
There are eight candidates, including Bertschi, left in the race. A ninth, Toronto lawyer George Takach, bowed out last month and threw his support to front-runner Justin Trudeau.
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