The vacant Pembroke seat in the Legislative Council, left by gravely ill Vanessa Goodwin, will be filled by one of seven candidates for the remainder of the house’s term, which is set to end in 2019.

The three main contenders for the seat are seen by many to be Liberal candidate James Walker, Independent Doug Chipman and Labor candidate Joanna Siejka.

The leading trio is joined by Greens candidate Bill Harvey and three independents – Carlo Di Falco, Richard James and Hans Willink.

Psephologist Dr Kevin Bonham predicts a victory for Mr Chipman, followed by Ms Siejka, however recent developments may catapult Mr Walker into the role.

With nearly 3000 pre-poll votes and 1500 postal votes cast respectively, Tasmanian Electoral Commissioner Andrew Hawkley said he expected a big turnout for Saturday’s by-election.

However, according to Mr Hawkley only the first preference votes will be counted on Saturday night, with all the provisional counting, non postal votes, to be counted by Sunday night.

Mr Chipman enters the race as the incumbent mayor for Clarence City Council – a local government area that overlaps with the state government electorate of Pembroke.

He was also elected Local Government Association of Tasmania chairman in 2014, however, he stepped down from the position during the campaign.

Dr Bonham said he believed Mr Chipman’s standing as mayor of the electorate made him the favourite in the by-election race.

“I think that Chipman has to be the favourite on paper, based on the history of mayors doing very well in these legislative council elections,” Dr Bonham said.

“For a lot of these local elections, local name recognition is a factor.”

Mr Walker also garnered a level of name recognition from the local constituents thanks to his role as an alderman on the Clarence City Council.

Meanwhile, Ms Siejka comes into the election as Youth Network of Tasmania chief executive.

The key issue of the electoral race for many is the state government’s takeover of TasWater, with Dr Bonham describing it as the “noisiest issue of the election”.

While Mr Walker stands with the government in its takeover attempts, Mr Chipman has been vocal in his opposition to the proposed move to poach the local government-controlled entity.

In April, he labelled the potential takeover as “appalling”.

However, his strong stance on the issue came back to bite him during the Pembroke campaign after an E.Coli outbreak occurred in Mr Chipman’s own backyard at the Risdon Vale reservoir.

The outbreak in the Hobart suburb lead to a boil water alert earlier this week.

In the wake of the announcement, key Liberals, such as Treasurer Peter Gutwein and Health Minister Michael Ferguson, said the boil water alert was an indictment on the local government’s handling of TasWater. 

If Pembroke votes for their incumbent mayor, however, it could be seen as a push back against the government’s plan to seize control of TasWater, according to Dr Bonham.

Pokie machines have also been a hot button item during the campaign, in the wake of a parliamentary inquiry into the gaming machines.

Despite calls from The Greens and some Labor members for a complete ban on poker machines in pubs and clubs, the Liberal government said it would not impose any such ban.

Greens candidate Bill Harvey has campaigned on a no pokies platform, calling for a complete ban on pokies in pubs and clubs.

Mr Harvey is the only candidate to endorse such a ban.

Ms Siejka, meanwhile, has not made her stance clear on poker machines.

Many analysts believed a victory for either the Labor or Liberal candidates would serve as a predictor for next year’s state election.

Recent polls had Labor leader Rebecca White leading Premier Will Hodgman as the preferred premier.

Dr Bonham said a continuation of this momentum could sweep Ms Siejka into the Legislative Council.

“If Labor wins this one it'll be very difficult for the Liberals to win a majority next year,” he said.

“If Labor win their stocks are looking better than expected going into the state election.

“If the Liberals do win this one, it would mean that they are in a stronger position than people expected, and you'd have to question the efficacy of some of the state polling.​ 

“Chipman winning doesn't tell us anything about the state election. If he wins, it's another conservative Liberal leaning independent elected - nothing to see here, move on.​”

The by-election campaign has been notable for the Liberal Party’s attacks on Mr Chipman’s age, 71, which he described as “nasty”.

The state Liberal Party disseminated media releases questioning if Mr Chipman was too old to serve in the position, and also took a jab at his age through a photoshopped twitter post.

The post depicted a supposed collection of Mr Chipman’s possessions – golf clubs, grandpa slippers, a fishing rod and a vinyl of 1940s singer Perry Como.

Mr Walker, however, distanced himself from these attacks.

But Dr Bonham does not believe this would be an effective tactic when the votes are counted.

“I don't think it's going to convince a lot of people not to vote for Chipman,” he said.

“There would be the odd person who would go, 'oh I didn't know he was that old, i'm not going to vote for him', but I think he'll get at least as many votes back in sympathy in the other direction.​”

Ms Siejka ran a more traditional campaign, focusing on door knocking throughout the constituency. 

This is a tactic Labor Leader Rebecca White emphasised in recent times, and if successful could provide a template for Labor’s election campaign next year.