First there were free Krispy Kreme donuts for vaccinated Americans. Then there were free beers. Now, more and more states are rolling out $1 million dollar cash lotteries as incentives for Americans to get vaccinated.

Ohio was the first to roll out its so-called "Vax-a-Million" campaign on May 13, which offered vaccinated adults a chance at one of five jackpots each totaling $1 million if they received at least their first dose. According to the state's Department of Health, the incentive was enough to quickly spark a 28% spike in vaccinations.

Other states across the country have been quick to adopt Ohio's lottery incentive and the other incentive that followed for non-adults: Ohioans aged 12 to 17 who received at least one dose of the COVID-19 vaccine were also eligible to win one of five four-year full-ride scholarships at any Ohio state college or university. Similarly, New York Gov. Andrew Cuomo announced this week that any state resident between 12 and 17 years old who gets a first dose of the Pfizer-BioNTech vaccine starting on May 27 would be entered into a raffle to win a full scholarship to a New York public university.

Last week, Maryland and Oregon followed with lotteries of their own for vaccinated adults. This week, Colorado and New York put their money behind their vaccine pushes with their own lotteries as well, offering five $1 million prizes and even scratch-off tickets. On Thursday, California topped them all with a top prize of $1.5 million reserved for 10 lucky vaccinated Californians to be picked on June 15.