Liberal Zed Seselja has fallen fractionally below one third of the primary votes as counting continues in the tight ACT Senate race.
However Mr Seselja remains well ahead of the Greens' Simon Sheikh in the race for the second Senate seat.
As well, the Liberal Party can rely on thousands of preference votes from several minor parties.
A striking outcome of the ballot is the approximately 30,000 votes cast for minor parties.
Labor's Kate Lundy retains a Senate seat, despite a swing against Labor.
The Australian Electoral Commission is entering data from tens of thousands of below-the-line ballots, which is estimated to take at least all this week.
After these votes are in the commission's computer, preferences will distributed.
The Greens say a significant proportion of their supporters voted below-the-line.
On Tuesday afternoon the commission had counted 84.24 per cent of the vote.
Senator Lundy had 34.42 per cent of primary votes, Mr Seselja had 32.89 per cent and Mr Sheikh had 19.48 per cent, an improvement on his 18.8 per cent last Friday.
Mr Sheikh tweeted on Tuesday: ''AEC has informed me that this stage of counting will take until October 1st. Could be a few more weeks before preferences are distributed.''
The quota to win one of the territory's Senate seats is set at one third of the vote, and will be calculated when all the votes are counted.
Mr Seselja is speaking more confidently of victory in the ACT Senate race, after being welcomed into Friday's meeting of Coalition MPs.
He said it seemed almost mathematically impossible for the Greens to overtake him.
The Animal Justice Party, which has first place on the ACT Senate ballot paper, is directing its preferences to the Liberal Party. It put the Greens last in retaliation against ACT Greens MLA Shane Rattenbury, the Minister for Territory and Municipal Services, who authorised the cull of about 1450 kangaroos recently to protect rare grasslands.
The Rise Up Australia Party is directing its preferences to the Liberals. The Stable Population Party has three tickets, two with preferences for the Greens, one for the Liberals.
The other minor parties directing preferences to the Greens over the Liberal Party are Katter's Australian Party, Bullet Train for Australia, Drug Law Reform, Sex Party, Voluntary Euthanasia Party, Palmer United Party and Australian Independents.
Late Tuesday, Mr Seselja had 71,897 and Mr Sheikh had 42,589 of the 223,377 votes counted. The commission says 265,160 voters were enrolled at the close of polls.
If the Liberal Party receives all the preferences from Rise Up and Animal Justice and one third of the preferences from Stable Population Party, Mr Seselja would have an extra 4155 votes, bringing his support to 76.052 at this point in the counting.
If Mr Sheikh receives all the preferences from minor parties favouring the Greens, he would receive an extra 24,277 votes, bringing his support to 66,866 votes.
In the 2010 election, Senator Lundy received 92,271 first preference votes, then Liberal senator Gary Humphries received 75,576 and Greens candidate Lin Hatfield Dodds received 50,600.