Deputy Prime Minister Barnaby Joyce faces the prospect of losing his New England seat after just one term as the first opinion polling in the sprawling country electorate shows voters swinging behind the former local member, independent Tony Windsor.
And it could be the issue of coal mining in prime farm land, which is opposed by both men, that is fuelling the backlash.
Windsor vs Joyce in battlefield New England
Crime syndicates rort visa programs
Election 2016: Bishop on the attack
Election 2016: Shorten vs Shorten
Australian visa schemes 'produce fraud'
Violence erupts in Melbourne protests
Labor's costings: do they add up?
Labor's cheeky relaunch
Windsor vs Joyce in battlefield New England
Former independent MP Tony Windsor will try to wrest his old seat of New England from Deputy Prime Minister Barnaby Joyce. Vision ABC News 24.
Exclusive ReachTEL polling of elector sentiment obtained by Fairfax Media - the first such voter-feedback in the crucial electorate - shows primary support for Mr Joyce stands at an apparently healthy 43.1 per cent, compared to Mr Windsor, who trails on 38.
But with the likelihood of strong preference flows from anti-Coalition Labor voters, who constitute 7.1 per cent, and equally hostile Greens voters who account for another 3.4 per cent, there is a reasonable chance Mr Windsor would finish ahead, were a contest held now.
The automated telephone survey of 662 residents across New England was conducted on the evening of March 10 - the very same day Mr Windsor declared his candidacy.
It has a margin of error of 3.9 per cent, plus or minus.
The poll's result suggests the entry of Mr Windsor, who held the seat until 2013, will push Mr Joyce to the limit in a local contest that threatens to consume much of the time he would otherwise spend on broader national campaigning as his party's leader.
The independently conducted ReachTEL survey was commissioned by left-leaning think tank The Australia Institute, as part of its ongoing monitoring of voter attitudes to new coal projects and broader economic policy issues.
With the Shenhua coal mine going ahead in the electorate, the survey found that 62 per cent of electors either oppose the $1.2 billion project going ahead on the Liverpool Plains (19 per cent) or strongly oppose it (43.1 per cent).
By contrast, those who either support the mine (15.3 per cent) or strongly support the mine (11 per cent) constitute just 26.3 per cent of voters.
"Coal is politically toxic in New England. Nearly half of respondents declared themselves 'strongly opposed' to the Shenhua mine, which will not be good news for pro-coal candidates," said the Australia Institute's executive director, Ben Oquist.
"In farming communities on the front lines of the expansion of the coal industry, there is a growing movement for greater rights for farmers and opposition to mines in fertile agricultural areas."
Both candidates oppose the mine, however, Mr Windsor believes he is better placed to campaign on the issue as he is not a senior member of the government that had approved it.
Mr Joyce, who last month became Nationals leader and therefore Deputy Prime Minister, had argued against the mine in his capacity as Agriculture Minister.
"It's my view as the agriculture minister, I'm sort of agnostic about whether it's in my electorate or not," he told Radio National in July 2015.
"If somebody said we are going to put a mine in the middle of [another] plain I would say that's not a good spot for a mine, that is a bad decision."
At the time he also cast doubt on the sincerity of Mr Windsor's opposition to the project, saying: "I always find it surprising that someone who is a multimillionaire, because he sold his property to a coalmine, is now the champion talking about stopping a coalmine."
The bleak news for the Turnbull government's second-most-senior figure, comes as Prime Minister Malcolm Turnbull winds up the pressure for an election, issuing an ultimatum to the Senate crossbenchers, telling them to pass blocked anti-union corruption bills or face a double-dissolution election in which most will be wiped out.
"The only reason to have a double dissolution is to resolve a deadlock," Mr Turnbull told the ABC on Friday.
"It is clearly an option and it is something that the government is considering.
"The way to take that option away is for the Senate to pass those bills."
A double dissolution would almost certainly require the budget to be brought forward to May 3 from May 10, ahead of an election set for the first Saturday in July.
Both candidates enjoy high recognition within the community, with Mr Windsor famous - and vilified in conservative circles - for his parliamentary support of the Gillard minority government.
Tellingly, it finds that even among those describing themselves as Nationals voters, just 36 per cent favour coal mining whereas 52 per cent oppose.