The Animal Justice Party has claimed the final seat in the race for the New South Wales Upper House.

Its candidate Mark Pearson edged out the other minor party in the running, the No Land Tax Party.

The party was "formed as a response to growing public concern about the neglect of animals and animal protection issues by political parties", according to its website.

It opposes factory-farming, the transportation of live animals over long distances, their use in harmful experiments and "the killing and mistreatment of animals in sport, recreation and entertainment".

The party also wants to "develop a new legal status for animals which acknowledges their rights to live protected from human harm".

Its MLC-elect is a former psychiatric nurse who has campaigned against sheep mulesing and kangaroo meat exports.

Hazel Stevens from the Animal Justice Party said they knew it would be close, but were delighted with the result.

"We're absolutely overjoyed about this, we've worked really, really hard for it and we're absolutely delighted that Mark Pearson has got in," she said.

"It's absolutely fantastic news."

The party's national president and founder, Professor Steve Garlick, said the seat was won on a shoestring budget.

NSW Upper House MPs Coalition: 20

Coalition: 20 Labor: 12

Labor: 12 Greens: 5

Greens: 5 Christian Democrats: 2

Christian Democrats: 2 Shooters and Fishers: 2

Shooters and Fishers: 2 Animal Justice: 1

"We ran on a total budget of $12,000, and a lot of passion," he said.

Professor Garlick said, at one fundraiser, Mr Pearson put his operatic skills to good use and sang to raise money.

Upper House balance of power

Premier Mike Baird's Government only needs two crossbench votes to pass its legislation, including to privatise the state's electricity infrastructure.

The Christian Democrats claimed a second seat in the Legislative Council today, while the Shooters and Fishers also have two.

The Greens will have five MLCs.

ABC election analyst Antony Green said the result represented an improved position for the Government in the Upper House, even though it did not have a majority.

"Where in the old [Legislative] Council the Coalition needed the support of both the Christian Democrats and the Shooters and Fishers to pass legislation, the Government will now need the support of only one of the two smaller parties," he said.

"In the case of electricity privatisation, with all other parties committed to opposing the sale, the two key votes will be Christian Democrat MLCs Fred Nile and Paul Green."

The Christian Democrats have given conditional support to the Government's privatisation agenda, but first wants it scrutinised by a parliamentary inquiry.

Meanwhile, Peter Jones of the No Land Tax Party, who missed out on a seat by fewer than 4,000 votes, has repeated his intention to challenge today's result in court.

Mr Jones said he wanted the state to go back to the polls.

"Only a judge on the take or on crystal meth would not order a fresh election," he said.

Mr Jones said he was appealing on four grounds: the alleged harassment of party workers on voting day by the Liberal Party, improper use of taxpayer funded offices as campaign offices, the glitch in the iVote system, and the pre-funding system which grants money to existing parties before the election.