Three-quarters of Ontarians oppose the looming 13 per cent harmonized sales tax, suggests a new Toronto Star-Angus Reid Public Opinion survey.

In troubling news for Premier Dalton McGuinty's Liberals, 70 per cent of the 1,162 people polled said their opinion of the government has worsened due to the HST.

The numbers were released on the first day of public hearings into the tax at Queen's Park, where various interest groups converged, and about 300 First Nations peoples held an anti-tax rally on the front lawn and later blocked evening rush-hour traffic on University Ave. and College St.

"This is where we have to draw a line in the sand," said Grand Council Chief Patrick Madahbee of the Union of Ontario Indians, calling for aboriginals to be exempt from the tax at cash registers.

The HST will put a "great burden" on aboriginal peoples, many of whom live in poverty, particularly in Northern Ontario where the cost of goods is already too high for many without the extra tax, added Grand Chief Stan Beardy of the Nishnawbe Aski Nation.

The online poll also found that 76 per cent of respondents are familiar with the tax, which melds the 8 per cent provincial sales tax with the 5 per cent federal GST as of July 1. That means an extra 8 per cent tax on many items that are now exempt from it but are already subject to the HST.

The poll, conducted Nov. 23 to 26, is considered accurate to within 2.8 percentage points.

With 75 per cent opposing the tax and five out of six 83 per cent predicting it will make goods and services more expensive, it's clear the government's message that the business-friendly levy will boost the economy is not taking hold.

Finance Minister Dwight Duncan acknowledged his government's sales job on the tax, which it estimates will create 600,000 jobs by streamlining costs for business, has a long way to go.

"We still have a lot of work ahead of us to help educate Ontarians about this," Duncan told reporters, blaming "misinformation" from opposition parties for telling only part of the story.

"It's a very complicated package."

Duncan said he and Premier Dalton McGuinty have written to their federal counterparts asking Ottawa to grant the exemption the First Nations requested.

At the public hearings, a legislative committee heard a litany of complaints about the tax that will increase the price of gasoline, heating fuel, haircuts, taxi fares, and hundreds of other goods and services.

"We are opposed to new taxes, which is what the HST is to bowling," said Sue Cannon of the Bowling Proprietors Organization of Ontario, who noted laws permitting Sunday shopping and banning indoor smoking have already hurt her industry.

Others, including the Ontario Chamber of Commerce and Ontario Trucking Association, came out strongly in favour of the tax, which Duncan says will be offset by personal income tax cuts taking effect Jan. 1 and rebate cheques in the next two years.

"What's uppermost on people's minds right now is jobs and future jobs," said David Bradley, president of the Ontario Trucking Association. "And unless we get the tax system right here we're not going to be able to make sure those jobs are there."