WASHINGTON — The U.S. is set to meet President Joe Biden's latest vaccine goal of administering 200 million coronavirus shots in his first 100 days in office, as the White House steps up its efforts to inoculate the rest of the public.

With more than 50% of adults at least partially vaccinated, Biden on Wednesday will reflect on his efforts to expand vaccine distribution and access in his first three months in the White House. But with all those 16 and older now eligible for shots, the president is expected to outline his administration's plans to drive up the vaccination rate even further.

With roughly 28 million vaccine doses being delivered each week, demand has eclipsed supply as the constraining factor to vaccinations in much of the country. While surveys have shown that vaccine hesitancy has declined since the rollout of the shots, administration officials believe they have to make getting vaccinated easier and more appealing.

Maximizing the number of Americans vaccinated in the coming months is critical for the White House, which is aiming to restore a semblance of normalcy around the July Fourth holiday and even more so by the beginning of the next school year. 

Biden was not expected to set new public targets for vaccinations, and administration officials have been careful to avoid predicting when the country will have vaccinated enough people to reach herd immunity. The U.S. is on track to have enough vaccine supply for every adult by the end of May and for every American by July, but administering the shots will be another matter.

In recent weeks the White House has launched a massive outreach campaign to Americans to get vaccinated, relying on funding from the $1.9 trillion virus relief package passed last month to launch ads and fund direct community engagement to under-vaccinated constituencies.

Biden set his goal of 200 million shots last month after meeting his 100 million-in-100 days goal just over a month ago. At the time the U.S. was well on pace to meet the higher target, and the pace of vaccinations has only accelerated, to about 3 million shots per day.

The 100 million-dose goal was first announced on Dec. 8, days before the U.S. had even one authorized vaccine for COVID-19, let alone the three that have now received emergency authorization. Still, it was generally seen within reach, if optimistic.

By the time Biden was inaugurated on Jan. 20, the U.S. had already administered 20 million shots at a rate of about 1 million per day, bringing complaints at the time that Biden's goal was not ambitious enough. Biden quickly revised it upward to 150 million doses in his first 100 days.

It was a deliberate effort by Biden to set clear — and achievable — metrics for success as part of a strategy of underpromising, then overdelivering. Aides believe that exceeding his goals breeds trust in government after the Trump administration's sometimes fanciful rhetoric on the virus.