SYDNEY • Australia's former deputy prime minister Barnaby Joyce yesterday cleared the way for his return to Parliament, winning a by-election just over a month after he was kicked out over a dual citizenship crisis that cost the government its majority.

Mr Joyce won about 63 per cent of the vote for the New England seat in New South Wales, compared to 11 per cent for his nearest rival, with around half of the votes counted.

In last year's election, he took 52 per cent of the vote. The win gives Prime Minister Malcolm Turnbull a welcome boost after a tough few weeks.

"This has been a stunning victory," Mr Turnbull told supporters as he joined Mr Joyce at a pub in the town of Tamworth.

Exit polls were predicting "the largest swing to the government in the history of by-elections in Australia", Mr Turnbull said, adding that it was a vindication of his coalition.

In an interview with Sky News after claiming victory, Mr Joyce said: "We want to show the Australian people that we're back in business."

Mr Joyce, 50, was one of the "Citizenship Seven" whose eligibility to sit in Parliament was thrown into doubt when it was found they were dual citizens, a status that is barred for politicians under Australia's Constitution to prevent split allegiances.

The High Court ruled on Oct 27 that Mr Joyce, along with four of the other lawmakers, was ineligible to remain in Parliament, forcing a by-election.

Mr Joyce was found to be a dual citizen of New Zealand, a status he has since rescinded.

The deputy leader position, traditionally held by a member of the junior coalition partner, the National Party, had remained vacant since the High Court ruling. The result comes at a difficult time for Mr Turnbull, who last week reversed his long-held opposition to a full-blown inquiry into the country's scandal-hit financial sector amid mounting political pressure.

Mr Turnbull has also seen a splinter within his centre-right Liberal-National coalition over same-sex marriage, with the conservative faction, led by some of the Nationals, angered by his promise to push though legislation after an historic public vote in favour of the unions.

The last day of campaigning for the by-election was marred by a call from New South Wales Nationals state leader and deputy premier John Barilaro for Mr Turnbull to step down as a "Christmas gift" to the nation.

The comments were quickly rebuffed by Liberal Party lawmakers and Mr Joyce, who said they were "very unhelpful" and "insulting".

REUTERS, BLOOMBERG