Tasmania's Liberal government will back a new $700 million hydro-electric power station if re-elected at the state election.
The party on Tuesday announced plans to double the capacity of the Tarraleah station in the Central Highlands to 220 megawatts by building a new facility on the same site.
The project is contingent on the Commonwealth contributing $65 million, with the remaining $635 million to be funded by state-owned Hydro Tasmania.
"In terms of the fact we'd be putting in over 600 million ... the least the Commonwealth could do (is) support us with this project," Premier Peter Gutwein told reporters.
The four-year construction is expected to create 250 jobs at its peak, with the build slated to start in 2022 if the funds are secured.
The power station was commissioned in the 1930s and currently generates 630 gigawatt hours of energy each year, about 6.5 per cent of Hydro Tasmania's total production.
The Labor opposition, meanwhile, focused on health as campaigning enters its final stages before Saturday's poll.
The party pledged to employ more midwives and specialist doctors to deliver maternity services at the northwest Mersey Community Hospital.
"For seven years the Liberals have failed to deliver better outcomes for both patients and staff," Opposition Leader Rebecca White said.
Recent voter surveys indicate the election, in which the Liberals are chasing a third term, could be a tighter race than initially predicted.
Ms White won over a room of undecided voters in Hobart during the final leaders debate on Monday.
"The only poll I'm focused on is the one on Saturday," Mr Gutwein said when asked about the forum.