SPRINGFIELD — A four-year effort by lawmakers and advocates to raise the minimum age to purchase tobacco products in Illinois to 21 appears nearly complete now that legislation approved by both chambers heads to Gov. J.B. Pritzker’s desk.

The Senate successfully passed the measure Thursday by a mostly party-line vote. It received the backing of only one Republican.

Pritzker has not said definitively whether he will sign “Tobacco 21,” which changes the age to buy products containing nicotine — including cigarettes, e-cigarettes, vapes and chewing tobacco, among others — from 18 to 21.

In an emailed statement, his spokeswoman said Pritzker “looks forward to reviewing the legislation.”

But supporters of the initiative are optimistic the Democratic governor will sign the bill into law, unlike former Gov. Bruce Rauner, who vetoed a similar measure last year.

“Thankfully, we’ve got a new governor and a new chance to right past wrongs and make Illinois a healthier state,” Senate President John Cullerton, a Chicago Democrat and ardent supporter of the legislation, said in a press release.

If Pritzker signs the bill, Illinois would be the eighth state in the nation, and the first state in the Midwest, to have such a law on the books.

Cullerton was on the floor of the House when that chamber approved the “Tobacco 21” legislation with bipartisan support Tuesday. The final tally in the House was 82 to 31.

And House sponsor Camille Lilly, a Democratic representative from Chicago, was on the floor of the Senate Thursday watching as her Senate colleague, Julie Morrison, secured enough Democratic votes to successfully pass the bill there.

The final vote in the Senate Thursday was 39 to 16.

Morrison, from Deerfield, is the sponsor of the initiative in her chamber.

“Senator Morrison did a wonderful job staying the course, going along with the different strategies and getting it done,” Lilly said. “It takes all of us. That’s what makes it difficult, but this is an amazing process.”

Opponents made the same two arguments they have in committee hearings and in the House. First, that if 18 is old enough to get married, vote in a political election, open a bank account and join the military, it should be old enough to purchase and smoke a cigarette.

But Morrison argued that the U.S. Department of Defense is going tobacco free by 2020, and a national group of hundreds of retired senior military officers, called Mission: Readiness, supports this “Tobacco 21” bill out of concern for the readiness of new recruits for the Armed Forces.

“I think this speaks volumes about what the military would, in fact, want for its members,” Morrison said.

Detractors also take issue with the removal of language from current law enacting penalties for minors caught with tobacco products. Presently, minors risk the prospect of taking a “smoker’s education or youth diversion program” with their parents as well as the possibility of fines or community service.

“Right now, to say that these kids who are getting their cigarettes from other kids are now going to be allowed to do that freely and without any punishment is a real problem,” Republican Sen. Steve McClure, from Springfield, said during debate.

Kathy Drea, the American Lung Association’s senior director for advocacy, said there is “absolutely no research” demonstrating penalties reduce the smoking rates among teenagers.

“It’s as simple as that,” she said.

Lilly said the Senate’s vote Thursday was “exciting and encouraging” to watch.

“When things get out of hand or are no longer tolerable, the people speak and we as legislators come to bring that message and advocate — that’s what we did today,” she said. “I get to have this be part of my history. I believe this is one of those bills that saves lives.”