The findings provide more evidence that Americans remain worried about the threat of the virus and cautious about efforts to lift stay-at-home restrictions and to reopen businesses, even as many governors have begun to move in that direction. In the face of plans in many states to gradually ease those limitations, significant majorities of Americans continue to emphasize the need for social distancing and other safety measures.

Fully half of all Americans say in the poll that they think it will not be safe for gatherings of 10 or more until midsummer, including nearly one-quarter who say it will not be safe until 2021 or later. Just about 1 in 5 say they believe such gatherings are safe now or will be by the end of this month.

The timeline has shifted substantially in just the past few weeks, as the number of covid-19 cases and deaths continue to rise. In a similar poll in mid-April, 51 percent of all Americans said they thought gatherings of 10 or more people would be safe by the end of June. That has fallen to 32 percent in the latest survey, with 66 percent saying it will take longer for gatherings to be safe.

Democrats still envision a longer timetable before safe gatherings can occur than do Republicans, with 80 percent of Democrats and 54 percent of Republicans saying opening by the end of July or later now seems likely. But there has been a shift in perceptions across the political spectrum since mid-April. Among both Democrats and Republicans, the percentages who say gatherings won’t be safe until July or later have risen by 26 percentage points. Among independents, the increase is 14 points.

The findings about safe gatherings continue to be heavily shaped not just by partisanship, but also by persistent personal concerns about contracting the virus and becoming seriously ill as a result. Overall, 58 percent of Americans say they are very or somewhat worried about getting the infection and becoming seriously ill, down from 63 percent last week but similar to 57 percent three weeks ago. Among those Americans who worry about getting the virus, 80 percent say it will not be safe for gatherings of 10 or more people before July, with most of them saying it will be later this year or beyond. Among those not particularly worried, 51 percent say they think gatherings of that size will be safe by the end of June, and more than 1 in 3 say it will be safe by the end of this month.

Although Republicans and Republican-leaning independents are significantly less worried about becoming seriously ill — 44 percent compared with 68 percent of Democrats and Democratic-leaners — those worries carve sharp divisions within partisan groups. Among Republicans who are less worried about becoming sick, more than 6 in 10 believe gatherings of 10 or more will be safe by the end of June. But among Republicans who are personally worried, more than 7 in 10 expect it to take until at least July.

Despite the visibility of angry protests over coronavirus closures, most Americans remain cautious about reopening their state economy. A 58 percent majority say current restrictions on restaurants, stores and other businesses in their state are appropriate, with 20 percent saying they are not restrictive enough and 21 percent saying they are too restrictive. In late April, 66 percent said such restrictions were appropriate, 16 percent said they were not restrictive enough and 17 percent called them too restrictive.

Republicans are significantly more likely than Democrats to say the limitations on restaurants, stores and other businesses are too restrictive, with 35 percent of self-identified Republicans and Republican-leaning independents saying this compared with 9 percent of Democrats and Democratic-leaning independents.

At the same time, those who fear becoming ill from the virus are more than twice as likely to say the limitations are not restrictive enough as those who are not worried, 27 percent compared with 12 percent.

With more than half the states moving to reopen their economies, and other data showing more Americans on the move even in the face of shelter-at-home orders, the poll finds widespread support for people in communities to practice social distancing, wear masks outside and follow other practices health officials have recommended to mitigate the spread of the coronavirus.

Eight in 10 say it is necessary for people in their communities to wear a mask when outside the home, and more than 8 in 10 say it is important for people to stay at least six feet apart from one another in public. Three in 4 say people in their communities should avoid gatherings with friends with whom they do not live, and more than 3 in 4 say people should stay at home as much as possible.

Clear majorities of Democrats, Republicans and independents support such measures, although about a third or more of Republicans say wearing masks, avoiding gatherings with friends and staying home as much as possible are unnecessary. Just over 1 in 5 Republicans say keeping six feet apart is unnecessary.

“The widespread belief that people should wear masks and restrict their contact with people outside their homes is striking,” said Michael Hanmer, a professor of government and politics at the University of Maryland who co-directed the survey. “This stands in stark contrast to the handful of crowds in close spaces that have gained media attention.”

Overall, 55 percent of Americans currently say they think people in their communities are striking the right balance on practicing social distancing, but 33 percent say people are not taking those practices seriously enough. Democrats are more likely than Republicans or independents to say they do not think people in their communities are taking social distancing practices seriously enough, with concerns also peaking among people who are personally worried about becoming seriously ill.

The poll was conducted by The Washington Post and the University of Maryland’s Center for Democracy and Civic Engagement. Interviews were conducted May 5 to 10 among a random national sample of 1,007 adults, 70 percent of whom were reached on cellphones and 30 percent on landlines. Overall results have a margin of sampling error of plus or minus 3.5 percentage points.

Emily Guskin and Alauna Safarpour contributed to this report.