More than 80 percent of respondents in one representative poll from the University of Michigan said they supported a ban on smoking in cars when children under the age of 13 were present.

The findings accompany other statistics showing that 87 percent of adults support a ban on smoking in businesses where children are allowed, along with 75 percent supporting no smoking in homes where an asthmatic child is present. Perhaps most surprisingly, 60 percent of smokers said they supported a ban on smoking in cars carrying children.

The team's poll included 1,996 subjects 18 years of age and older, at a 58 percent completion rate. The poll was stratified to reflect the total U.S. population according to the most recent figures from the Census Bureau.

"Smoke is a real health hazard for kids whose lungs are still developing," said poll director Dr. Matthew Davis in a university news release, "and especially for kids who have illnesses like asthma where the lungs are particularly fragile and flare up when exposed to secondhand smoke."

Not only do children experience added health risks when exposed to secondhand smoke, the presence of a smoker also often dooms a child to pick up the habit before leaving adolescence.

"The younger the age of uptake of smoking, the greater the harm is likely to be because early uptake is associated with subsequent heavier smoking, higher levels of dependency, a lower chance of quitting, and higher mortality," states a 2013 fact sheet from Action on Smoking and Health. "Children are also more susceptible to the effects of passive smoking. Parental smoking is the main determinant of exposure in non-smoking children."

Although smoking rates have been cut in half since 1965, secondhand smoke still affects an average of 88 million nonsmoking Americans, according to the Centers for Disease Control and Prevention.

Currently, 40 of the 50 U.S. states have official bans on smoking in places of work and business, in addition to public transportation and parks. Seven states currently have bans on smoking in cars carrying children, including Arkansas, California, Illinois, Louisiana, Maine, Oregon, and Utah.

Meanwhile, four states — Hawaii, Indiana, New Jersey, and New York — have enacted citywide or countywide bans on smoking in vehicles where children are present.

"Given the high level of public support for laws prohibiting smoking in vehicles with children in this poll," Davis said, "it may be that the bans enacted by a small number of states should be considered by many more states, and perhaps at the national level."

While regulating such a ban may pose difficulties to the individual states, Davis' team has cited several precedents that, going forward, could prove useful in the fight to end childhood exposure to secondhand smoke and passive smoking — including smoking bans on commercial flights and federal buildings, to name a couple.

"High levels of support for banning smoking in vehicles with children present indicate that the precedent set by a small number of states, counties and cities may be ready for broader adoption across the country," the report states, noting that no states currently ban smoking in homes where a child with asthma is present. "However, the broad level of support in this Poll for such a policy raises the question of whether legislation on this topic may be possible in the future."