A telephone poll of 664 residents, conducted by ReachTel on behalf of the union United Voice, found 58 per cent opposed plans to cut penalty rates, with 17 per cent undecided.

Opposition was strongest among women and residents aged between 18 and 34, who are often more likely to work on a shift-by-shift basis.

More than half of surveyed residents said they were less likely to vote for a candidate who supported cuts to penalty rates, with 22 per cent unsure.

The poll was commissioned as part of an ongoing union campaign to protect penalty rates with prime minister Malcolm Turnbull describing them as outdated in October.

An earlier poll of 1183 Canberra and Queanbeyan residents by ReachTel on behalf of UnionsACT in October found 79 percent supported penalty rates, with 12 percent opposed and the remainder undecided.

Union representatives have also referred to a report by the McKell Institute, which found Monaro region workers could lose up to $16.8 million in wages a year if penalty rates were partially cut.The Productivity Commission has called for Sunday penalty rates be lowered to match Saturday payments for entertainment, hospitality and retail workers.

While the federal government has left the decision to the Fair Work Commission, ACT Liberal senator Zed Seselja has publicly called for the recommendation to be adopted.

The issue has also become a contentious one during the election campaign, with Greens leader Richard Di Natale criticising opposition leader Bill Shorten for vowing to respect the commission's decision.

The Canberra and NSW business chambers have also called for changes to Sunday penalty rates, claiming the lower costs would lead to more businesses opening on weekends and reducing youth unemployment.