For five Massachusetts adults and another five Bay State adolescents, the COVID-19 vaccine will prove to be an extra lucky shot.

The Baker administration will partner with Treasurer Deborah Goldberg and the Massachusetts Lottery to launch a "VaxMillions" giveaway in July, offering $1 million prizes to five adults 18 and older and $300,000 college scholarships to five adolescents between 12 and 17.

With the rate of new vaccinations slowing in recent weeks, officials unveiled the lottery on Tuesday -- the same day that Massachusetts surpassed 4 million residents fully vaccinated -- as the latest step in an effort to reach those who still have not been immunized against the highly infectious virus.

"We're hopeful that this giveaway will give another reason and opportunity for people to choose to get vaccinated here in the commonwealth over the next couple of months," Baker said.

States that implemented similar lotteries experienced "a significant increase in vaccine sign-ups after they put this program in place," he said.

All Massachusetts residents who are fully vaccinated are eligible to enter the drawing, including those who have been immunized for months, so long as they received their doses in the Bay State. Winners will have their names publicly disclosed.

Registration for the contest will start on July 1 and remain open through Aug. 20. Residents will need to submit their personal information online or via a soon-to-launch call center, and state officials will conduct one drawing for each prize per week between July 26 and Aug. 27.

Anyone who signs up in the process consents to the Department of Public Health accessing their vaccination records to verify they are indeed fully vaccinated, and those selected as winners may also be asked to provide their Centers for Disease Control-issued record cards or other information.

"If you're not vaccinated, you can't play," said Goldberg, who oversees the Lottery.

The Massachusetts State Lottery Commission will convene a special meeting at 11 a.m. on Thursday to vote on providing "technical and program support" for the VaxMillions giveaway. Massachusetts will pay for the lottery program from the billions in federal aid it received in the American Rescue Plan Act, Baker said.

Several other states such as Ohio and California have already offered lottery prizes to encourage vaccination in recent months. Baker said he spoke about the program with Ohio Gov. Mike DeWine, who told him the effort "created a lot more visibility around getting vaccinated generally" for a sustained period of several weeks.

"They did start to see pick-up rates among some of the populations they'd had a really hard time reaching, especially young people, mostly men between the ages of about 20 and 40, which is a tough population for us as well as it was for them," Baker said. "They also saw a lot of parents who are interested in this scholarship program, who use this as a mechanism to encourage their kids who may have not wanted to get vaccinated to get vaccinated."

Adults who have received both doses of the Pfizer or Moderna vaccine or the single-shot Johnson & Johnson vaccine will be eligible for the $1 million prizes. Adolescents between the ages of 12 and 17 must have received both of their Pfizer doses -- the only vaccine currently authorized for anyone below the age of 18 -- to qualify.

Scholarship winners will receive a $300,000 grant via a 529 College Savings Plan that the Massachusetts Educational Financing Authority manages, which Baker's office said "can be applied to cover tuition, room and board, and related expenses at any college, university, or technical or trade school or other post-secondary educational institution eligible to participate in a student aid program administered by the U.S. Department of Education." Any winners with a qualifying disability could choose to receive an equivalent award to a special needs trust or federally qualified ABLE account.

As of Tuesday, more than 4 million Massachusetts residents are now fully vaccinated against COVID-19. The Bay State is home to about 7 million people, and those under the age of 12 remain ineligible for the COVID-19 vaccine. More than 80 percent of the state's adults have received at least one dose, Baker said.

With nearly one in five Bay State adults not yet immunized, the pace of vaccinations has dropped considerably. On May 1, the seven-day average of daily vaccine doses administered stood at 76,738, according to a News Service analysis of state data. By June 8, it had fallen to about 28,315.

The Baker administration, which lifted the state of emergency on Tuesday, pivoted in recent weeks from a mass vaccination campaign to a more targeted approach featuring incentives and expanded local outreach. Gillette Stadium administered its final doses on Monday, becoming the first of the state's seven mass vaccination sites to go offline.

Sizable gaps remain in vaccination rates by race and ethnicity. Through June 8, about 62.3 percent of the state's white population and 64.5 percent of the state's Asian population had received at least one dose, compared to only 46.9 percent of Black residents and 44.9 percent of Hispanic residents, according to the Department of Public Health.

Officials said the administration will continue contracts in 20 hard-hit communities with sizable populations of color through the summer for additional vaccine outreach and canvassing efforts.

"We are really working very, very locally, sort of referred to as hyper-focused on those communities where we need to continue to address vaccine hesitancy and bring vaccines as close as possible," said Health and Human Services Secretary Marylou Sudders. "What was the homebound program is now the in-home program, so we will literally bring vaccines to your home, as well as the temporary pop-up sites and the like."

The Baker administration has long targeted 4.1 million full vaccinations as its baseline goal. Asked Tuesday if he has a new goal in mind, Baker replied, "More. The new number is more."

Highly infectious variants of COVID-19 continue to spread, which Baker said "make this the kind of thing where we should do everything we can to get as many people vaccinated as we possibly can and not stop."

"From our point of view, we shouldn't stop," he said. "We should just do everything we possibly can."