Support for deporting undocumented immigrants has grown since Donald Trump was last in office, a review of recent polling finds – as have nativist sentiments more broadly. But the level of public backing for mass deportation varies significantly depending on the framing of the question, suggesting there are limits to the public appetite for denying any pathway to citizenship to people in the US illegally.

Trump made promises to carry out mass deportations a cornerstone of his 2024 campaign. His allies have already begun planning for ways to carry that out, while immigration advocates are bracing for sweeping actions.

CNN’s national exit polling this year found that immigration was a strong issue for Trump in this election, but it doesn’t suggest a mandate for mass deportation. Voters gave Trump a roughly 9-point advantage over Vice President Kamala Harris on trust to handle immigration, according to the latest data.

But they also said, by about 56% to 40%, that most undocumented immigrants in the US should be offered a chance to apply for legal status, rather than being deported to their home countries. One-quarter of Trump voters said they favored a pathway to citizenship, while only about 9% of voters who backed Harris said they wanted to see most undocumented immigrants deported. Nearly 4 in 10 of Hispanic voters who backed Trump said that they favored a path to citizenship.

Complicating those findings is the fact that polling this year has found widely disparate levels of support for deportation. Questions that simply ask whether people favor or oppose mass deportations find roughly half or more of the country in favor: 47% of Americans in a June Gallup poll said they favored “deporting all immigrants who are living in the United States illegally back to their home country,” and 58% of registered voters in an October poll from Marquette Law School backed “deporting immigrants who are living in the United States illegally back to their home countries.”

The Marquette poll, however, asked about deportation in two different ways. Half of the voters surveyed were instead asked whether they’d favor deporting those immigrants “even if they have lived here for a number of years, have jobs and no criminal record” – and support for deportation dropped to 40% among that group, with 60% opposing.

Similarly, a separate question in the Gallup poll found that 70% of US adults favored “allowing immigrants living in the U.S. illegally the chance to become U.S. citizens if they meet certain requirements over a period of time,” with an even broader 81% favoring a pathway to citizenship for those who were brought to the country as children.

And a CBS News/YouGov poll in June found that while 62% of registered voters favored starting a new national deportation program, a slim majority opposed the idea of holding immigrants in detention centers in order to do so.

Surveys that ask respondents to choose between deportation and a path to citizenship, meanwhile, often find more support for the latter. In CNN’s final pre-election survey this year, two-thirds of registered voters said that the government’s top priority for dealing with immigrants living illegally in the US should be developing a plan to allow some to become legal residents.

In a summer Pew Research Center poll, 59% of registered voters said there should be a way for undocumented immigrants who meet certain requirements to stay in the country, with 37% saying there should not be, and just one-third saying there should be a national law enforcement effort to deport all immigrants living illegally in the country.

Regardless of framing, however, national polls agree on a rise in support for deportation policies over recent years, coupled with a broader increase in nativist sentiment.

CNN’s October poll found support for deportation rising 20 points from 2017 among registered voters, with polling earlier this fall also finding a 22-point rise from 2019 in the share of voters who said that “having an increasing number of people of many different races, ethnic groups, and nationalities in the U.S.” was mostly threatening, rather than enriching, society.

In the June 2024 data from Gallup, the share of Americans who favored deporting all immigrations living illegally in the US was up 15 points from 2016, with the share favoring reduced immigration levels rising 17 points over the same time period.

As political scientist Michael Tesler noted earlier this year, that shift seemingly aligns with the “thermostatic model” of public opinion, in which “the public’s policy attitudes shift against the current president’s policies in response to real or perceived changes in the status quo … with their opinions moving to the left under Trump and back to the right under (Joe) Biden.”

This suggests views could move once again during Trump’s second term.

CNN’s Henry Gertmenian contributed to this report.