CNN  — 

President Joe Biden said Tuesday that he expected all states to open Covid-19 vaccine eligibility to all adults by April 19, and at the current pace of vaccination – about 3 million doses administered each day – every adult in the United States could be vaccinated by mid-summer.

But not every American plans to be vaccinated. While states such as New York and North Dakota might vaccinate all willing adults by June, it could take some states until the end of 2021 – and there are two very different reasons for that gap.

A survey conducted by the US Census Bureau found that at least one in six adults “probably” or “definitely” doesn’t plan to be vaccinated, and in some states up to a third of adults don’t plan to roll up their sleeves. Other surveys have found rates of vaccine hesitancy to be even higher, cutting the vaccination line down.

And in some states, the rollout of vaccines is just plain slow, even as many residents clamor for them.

As the race between Covid-19 variants and vaccinations continues, differences in vaccine hesitancy and the pace of vaccinations mean the race looks quite different state to state.

Some states may fully vaccinate all willing adults by June, but for others, it may take until the end of the year, a CNN analysis of federal data shows.

New York has one of the lowest rates of vaccine hesitancy in the country. About 85% of adults in the state either plan to be vaccinated or already have, according to a recent US Census Bureau survey. The state is also vaccinating at a pace that’s one of the fastest in the country, according to data from the US Centers for Disease Control and Prevention.

In the past week, New York has added nearly 146,000 people to the fully vaccinated group each day. At that pace – nearly 950 people fully vaccinated per 100,000 residents each day – and with nearly 4 million adults in the state already fully vaccinated, 85% of adults in New York could be fully vaccinated in about two months.

North Dakota is vaccinating at about half the pace of New York – about 570 people fully vaccinated per 100,000 residents each day – but might reach its vaccine capacity around the same time as New York due to high vaccine hesitancy rates. According to the Census survey, only about 68% of adults say they have been vaccinated or plan to, one of the lowest rates in the country.

Georgia and Alabama are vaccinating their populations at the slowest pace – fewer than 300 people fully vaccinated per 100,000 residents each day. In both states, about 75% of adults have been vaccinated or plan to be which would take the vaccination timeline into October for Alabama and November for Georgia.

In both Vermont and Massachusetts, about 92% of adults have been vaccinated or plan to be – more than any other state. But Vermont is vaccinating at a faster pace than Massachusetts and could vaccinate all willing adults by early July, about a month sooner than Massachusetts.

The most recent Household Pulse Survey from the Census Bureau was conducted in the first two weeks of March.

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For CNN’s analysis, adults were considered willing to be vaccinated if they have “received or plan to receive all required doses,” or if they have not yet been vaccinated but “definitely” or “probably” plan to. CNN calculated the pace of vaccinations using the most recent seven-day average of adults fully vaccinated reported by the CDC and population data from the Census Bureau’s 2019 American Community Survey.