Fiona Patten is still in the fight for Victoria's last Senate position on behalf of Legalise Cannabis, with the contest narrowing to a three-way battle involving Labor and One Nation.
Labor is still considered the frontrunner for the sixth seat, but Patten said her chances of an upset have improved over the past several days.
She cautioned, however, that the outcome will ultimately hinge on a "lottery" when preference allocations are finalised.
Patten said the voting "is trending upwards for us and downwards for Labor".
"As the second preferences start getting counted, they need to go to me at a much higher rate than they go to Labor, and that is quite likely," she said. "If someone hasn't voted for Labor as the first preference and supported a smaller party, they are unlikely to have made them their second preference."
Ahead of the election, Labor had encouraged its supporters to place Legalise Cannabis above other parties outside its own ticket.
Another potential boost for Patten is the cross-spectrum appeal of Legalise Cannabis policies, which could attract second-preference votes from both left- and right-leaning voters.
"A lot of pundits see us on the progressive side of politics. That might be the case for some of our MPs, but not necessarily among voters," she said. "It wouldn't be a surprise to see a Trumpet of Patriot voter or a Greens voter make us their second preference. We straddle both sides of politics and that may work in our favour."
Despite the encouraging signs, Patten acknowledged that the situation remains deeply uncertain.
"Really, there is no way of knowing how those preferences are going to flow until they press the button. At the end of the day, it's a lottery."
A final result could be known before the week is out.
