Labor is positioned to easily win the 22 February state government byelection in the Brisbane seat of Redcliffe, with public health a major concern for Queensland voters in state and federal polls early this year.

A new Lonergan Research poll of 891 voters found Labor’s Redcliffe candidate Yvette D’Ath – who lost the federal seat in the same area at last year’s election – on a huge 53% of the primary vote, well ahead of the LNP candidate and former Family First candidate Kerri-Anne Dooley.

The result of the poll, taken last week, is much more positive for Labor than a Reachtel poll commissioned by a state union and conducted on 13 and 14 December, which put Labor on 42.1% of the primary vote. Lonergan Research managing director Chris Lonergan said the polls were likely to “narrow significantly” as the campaign progressed.

Of those polled, 22% said “privatisation and outsourcing of the public health system” was the most important issue in their voting decision and another 59% said it was one of several issues important to them.

More than half (59%) said they thought Campbell Newman’s LNP government had made the state’s health system worse – including 10% of those who said they would vote for the LNP. Only 23% thought the LNP government, elected in a landslide victory in 2012, had made the health system better.

The byelection was triggered when former LNP MP Scott Driscoll was forced to leave state parliament in November and was fined $90,000 by parliament for being dishonest about his business dealings. But it will not be held until after the 8 February byelection in the federal Brisbane seat of Griffith, being vacated by former prime minister Kevin Rudd.

Health policy is also a focus of that campaign, in which the Coalition candidate is the former Australian Medical Association president Bill Glasson, who stood at the general election. Labor is fielding local lawyer Terri Butler.

Labor has seized on suggestions the federal government could introduce a $6 fee, or co-payment, for bulk-billed visits to a GP, a plan initially supported by Glasson. The government has made no announcement on the issue.

State unions have run a strong campaign against the Newman government’s plans to privatise the management of new hospitals.

Byelections are often used to deliver a protest vote to incumbent governments and federal polling since last year’s election has consistently revealed a slump in support for the Coalition.

A Roy Morgan poll, the first of the year, showed Labor at 52.5% federally on a two-party preferred basis, and the Coalition on 47.5% – confirming the trend in all major opinion polls late last year.

The deputy prime minister, Warren Truss, said on Tuesday the decline in popularity was because the Coalition had to make “tough decisions” and warned the government could decline even further in the polls.

The LNP holds Redcliffe by 10%. Labor holds only seven seats in the 89-seat state unicameral parliament. Rudd suffered a 5.4% swing against him at the federal election but held the seat with 53% of the two-party-preferred vote.

Lonergan Research conducted 891 surveys in automated “robopolls” across telephone exchanges within the Redcliffe electorate. The surveys were conducted between 9 and 12 January.