A teen-led initiative to lower the voting age in Lowell to 17 picked up momentum late last week after issues raised by state election officials regarding the petition’s constitutionality were put to rest.

A home rule petition that would have allowed Lowell voters last November to decide whether to allow 17-year-olds to participate in city elections only never made it to the ballot after Secretary of State William F. Galvin’s office determined that it was inconsistent with the state’s constitution, which requires voters to be at least 18.

Subsequent changes made to the bill had been under review by Galvin’s office until Friday, when a representative informed Lowell City Solicitor Christine P. O’Connor that the constitutional conflicts had been addressed, a Galvin spokesman confirmed. The finding could bolster legislative support for the bill, which, if passed, would be placed as a referendum question on the 2013 municipal election ballot for Lowell voters to decide.

If the petition makes the ballot and is approved, Lowell would become the only city in the country to give anyone under 18 the right to vote, according to the National Youth Rights Association.

“We’re feeling very encouraged that the language changes will make the bill even stronger,” said Gregg Croteau, executive director of United Teen Equality Center, the organization where local teens initiated the movement to lower the voting age, dubbed Vote 17. “The teens, they’ve always been focused on the fact that this bill was an incredibly intentional way to increase voter participation for years to come.”

With the state legislative session scheduled to come to an end July 31, teen organizers have scheduled a rally for 12:45 p.m. today in Nurses Hall, located on the second floor of the State House, to bring attention and garner support for the bill, which is in the final committee reading stage before it can make it on the House floor for a vote.

In order to make it to the November 2013 local ballot that would give Lowell voters the final say, the bill must be approved by the House and Senate and get the governor’s signature before July 31. But the teens aren’t sweating it.

“We’ve been very optimistic of what’s going on,” said Carline Kirksey, 17, one of the teens involved with the initiative. “We’ve been making sure we’re letting them know this won’t just affect 17-year-olds in Lowell, but Lowell itself.”

“I never thought adults or politicians would think too highly of teenagers,” said Yasley Cartagena, 18, who, like Kirksey, just graduated from Lowell High School. “This was a chance to show them there are thoughtful and intelligent teenagers. I’m quite optimistic.”

The changes to the bill’s language centered around concerns raised by Galvin’s office, including whether allowing 17-year-olds to vote would also make them eligible to run for office, and whether they would also be able to participate in regional local elections, such as for Greater Lowell Technical High’s school committee. The wording was changed to make it explicit that 17-year-olds would only vote for Lowell School Committee and City Council candidates, and could not run for office or vote in regional elections, O’Connor said.

Additionally, the bill now makes it clear that 17-year-old voters would be considered “special registered minors,” and would have to use a different ballot specifically printed just for them when participating in municipal elections, O’Connor said. Once they turn 18, their names would be stricken from the city’s special voter list, so they could then register as full-fledged Massachusetts voters.

Although the constitutional concerns have been satisfied, the secretary of state’s office still does not endorse the bill, said spokesman Brian McNiff. Galvin’s office recommended other changes to the bill, and made additional suggestions.

“What we have now is housekeeping issues and just some general questions regarding the timing and what we have to do, and when we have to do it by,” O’Connor said.

State Representative Kevin J. Murphy, a Lowell Democrat who sponsored the bill, said that although the petition does not have the support of the office that runs elections in the Commonwealth, he doesn’t think it’s necessary. He said he plans to update House counsel on the latest communication from Galvin’s office and proceed from there.

“We still have plenty of time to get it passed if we can everything in line,” Murphy said. “Voter apathy is one of the worst scourges in our process now, so the more people we can get out to vote, the better.”

Lowell Mayor Patrick O. Murphy, who led the home rule petition effort on the City Council, said he is hopeful the bill will make it past the legislative process and be sent to Lowell voters to make the final decision.

With the city coming off “the worst turnout in Lowell municipal election history,” last year, combined with a downward trend of participation statewide, Murphy said community leaders should be encouraged to, “engage the next generation.”

Kirksey and Cartagena, along with other local teens, will continue their aggressive social media campaign, as well as old-fashioned door-to-door visits, to expound on the benefits of giving 17-year-olds political franchise after today’s rally, which they consider their final big push before heading off to college this fall.

“For me, this has been an amazing experience,” Kirksey said. “I never thought that at 17 I would be doing this . . . This has been really hard, but at the end of the day, whether or not it goes through, I know that I did something successful.”