The state gas tax checked in as the least popular source of new revenue to fund Gov. Deval Patrick’s plan to invest in transportation and education, according to a new poll commissioned by the Campaign for Our Communities that found support for increased revenue.

Only 21 percent of voters said they approved of raising the state’s 21-cent gas tax by 15 cents, while taxes on cigarettes, candy and soda proved far more popular. The poll showed voters remain concerned about the economy, with 59 percent expecting it to remain the same or for economic conditions to worsen.

A 54 percent majority of voters said they would support raising the state’s income tax from 5.25 percent to 5.95 percent as long as the amount of income subject to the tax was also reduced. A smaller income tax increase to 5.75 percent without an increase in personal tax exemptions met resistance with 53 percent opposed to such a plan.

The Campaign for Our Communities is a coalition of unions, civic groups and advocates pressing for $2 billion in new tax revenue to support Patrick’s plan to invest heavily in transportation and education. The March poll conducted for the campaign by Boston pollster Tom Kiley surveyed 600 Massachusetts voters.

House Speaker Robert DeLeo has committed to finding new revenue to support investments in the state’s transportation system and Senate President Therese Murray said over the weekend that she’s looking at all revenue possibilities. Patrick is seeking $1.9 billion in revenues; lawmakers appear likely to seek an amount less than that.

Over the weekend, Murray expressed concern about overburdening the middle class with new taxes. “Is it a billion that we need? We haven’t agreed on what the gap is,” Murray said Sunday on WCVB’s “On the Record,” declining to indicate her preference for a source of new revenue.

The poll found that 76 percent of voters strongly or somewhat approve of Gov. Deval Patrick’s generic call for investments in infrastructure, transit and education, though just 54 percent approve of increases in state tax revenues in order to make those investments, compared with 43 percent opposed.

While DeLeo has expressed support for education spending, the speaker’s focus has been on crafting a financing plan to address the latest budget crisis at the MBTA, end the practice of using the state credit card to pay transportation employee salaries, and make infrastructure investments in roads, bridges and rail.

The poll, however, found greater support for a financing plan that also addresses education, with 61 percent backing a “broader plan” compared to 28 percent support for a narrower transportation-only fix.

When it came time to pay for the investments, 74 percent said they would support a $1 per pack increase in the cigarette tax to $3.21 and 61 percent supported extending the sales tax to candy and soda. Both tax increases, previously cast aside by the Legislature, were included as parts of Gov. Patrick’s overall tax reform plan.

Other options were far less popular. Fifty-six percent of voters surveyed said they oppose increasing tolls on the Massachusetts Turnpike by an average of 33 percent, and 64 percent opposed raising fares on the MBTA, commuter rail and local buses by 33 percent. The T raised fares in 2012 by an average of 23 percent.

DeLeo has said he has taken no options off the table, but groups like the Massachusetts Taxpayers Foundation have urged the Legislature to consider a modest gas tax increase and hikes in Registry of Motor Vehicle Fees to support the transportation system.

Seventy-nine percent of those polled opposed a 15-cent gas tax increase, compared to 21 percent in favor. An overwhelming 70 percent also said they opposed doubling the fee to register a car or renew a driver’s license, while 28 percent said they would support the increase.

Public opinions on the various tax options were measured against the backdrop of a recovering state economy with 32 percent of those polled indicating that they believe the economy is better than it was six months ago, while 48 percent said it was about the same.

Moving forward, 40 percent said they expect the economy to improve, 40 percent said it will stay the same, and 19 percent expect the economic conditions to worsen.