A plan to pump up to $1 trillion into infrastructure by luring private investors won’t win public support if it means new tolls on existing roads and bridges, according to a new poll.

In Washington Post-ABC News poll, 66 percent of those surveyed said they oppose a plan that would grant close to $140 billion in tax credits to investors who put their money into roads, bridges and transit in return for the right to impose tolls.

While the survey question made no mention of the incoming president, prior to the election Donald J. Trump proposed giving private investors an 82 percent tax credit to put money into projects, credits that theoretically would reduce their need to profit from the investment.

Trump said his plan would lead to up to $1 trillion worth of new projects. He said the more than $137 billion cost of the tax credit would balance out because tax revenue would be recouped by taxing the wages of people put to work on the projects and from taxes paid by contractors hired to do the work.

But even with tax credit incentives, investors are unlikely to put their money into projects that don’t provide a revenue stream, most likely in the form of tolls on roads and bridges.

The question asked in the Post-ABC poll was:

There is a proposal to offer nearly 140 billion dollars in tax cuts for private companies if they pay to build new roads, bridges and transportation projects. The companies then could charge tolls for people to use these roads, bridges and transportation. Do you support or oppose this proposal? Do you feel that way strongly or somewhat?

Only 29 percent of the 1,005 people polled said they would support that plan, with 11 percent saying they backed it strongly and another 18 percent saying they were somewhat supportive. In contrast, 44 percent said they were strongly opposed to the idea and 22 percent said they were somewhat opposed.

At her confirmation hearing last week, Trump’s nominee to head the Department of Transportation, Elaine L. Chao, addressed the issue of where funds will be found for infrastructure investment.

“As we work together to develop the details of the president-elect’s infrastructure plan, it’s important to note the significant difference between traditional program funding and other innovative financing tools, such as public- private partnerships,” Chao said. “In order to take full advantage of the estimated trillions in capital that equity firms, pension funds, and endowments can invest, these partnerships must be allowed to participate with a bold new vision.”

The thinking of Trump and Chao may be augmented by a new panel the president-elect is planning to review how the $1 trillion he expects to raise will be spent. In an interview with the Wall Street Journal on Friday, Trump said he plans name two real estate developers — Steven Roth and Richard LeFrak — to head the new panel.

The Post-ABC poll was conducted by telephone Jan. 12-15, 2017, including landline and cellphone respondents. Overall results have a margin of sampling error of plus or minus 3.5 percentage points.