Even though the country has opened up vaccine eligibility to anyone over the age of 16, Brownstein noted that there are still hundreds of millions of Americans who haven't received their shot and the tide will change as more people get their doses. As of Monday, more than 140 million people, roughly 42.5% of the U.S. population, have received one vaccine dose, and more than 95 million people, roughly 29% of the total population, are fully vaccinated, according to the CDC.