WASHINGTON — Seventy percent of U.S. adults have received at least one dose of a COVID-19 vaccine, a key milestone in the fight against the pandemic that the country hit nearly a month later than President Joe Biden had hoped.

After falling dramatically since April, the pace of U.S. vaccinations has recently accelerated due to the rapid spread of the delta variant of coronavirus. The U.S. was averaging more than 72,000 new infections a day in a delta-fueled resurgence of the virus as of Friday, according to the Centers for Disease Control and Prevention.

The administration reported Monday that 468,000 doses of vaccines were administered in the past day, including 320,000 to people getting their first shot, White House COVID-19 data director Cyrus Shahpar said on Twitter, calling the day a “Milestone Monday.” The first-shot number is up from 257,000 a week ago, he said.

The seven-day average of newly vaccinated people is 441,000, Shahpar also said. That’s the highest rolling average since June.

In early May, Biden set the 70% goal for Independence Day, believing it to be a reasonable threshold for the country to meet. But by the July Fourth holiday, only about 67% of adults had been given at least one dose.

The administration’s vaccination campaign has been marred by reluctance on the part of millions of Americans who don’t trust the shots, believe rampant misinformation they’ve read online or politically oppose the president.

Lower rates of vaccination are most common in areas of the country that strongly supported former President Donald Trump in last year’s election.

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