Most U.S. adults (9 in 10 Republicans and close to half of Democrats) say they support mass deportations of immigrants living in the country illegally — but that enthusiasm quickly erodes when presented with options over how to carry them out, according to a new Axios-Ipsos poll.

Why it matters: President-elect Trump has vowed to initiate one of the "largest mass deportations in U.S. history" starting early in his return to the White House. Beyond the logistical obstacles, costs and possible pain to the U.S. economy, the survey suggests Americans could quickly sour on deportations depending on how they are carried out.

By the numbers: Two-thirds of all Americans surveyed said they support deporting immigrants who are in the country illegally.

• Among Republicans, support was at 93%, followed by 67% for independents and 43% for Democrats.
• But just 38% of Americans support using active-duty military to find and detain undocumented immigrants in U.S. cities and towns; and only 28% want to use money allocated for the military to pay for deportations.
• Just one in three endorse separating families or sending people to countries other than their country of origin in the interest of speed. And just one in three support deporting those who came to the U.S. as children.
• The trends largely track with findings from a Ipsos-Syracuse University poll from November from which the questions were replicated. But the new survey shows even less support for use of active-duty military, or military funds, than the survey from two months ago.

What they're saying: "There's essentially broad agreement with Trump's position on these topics, but as soon as you start pushing into specifics, a lot of that dissipates," said Chris Jackson, Ipsos pollster and senior vice president.

• The concept of mass deportations may work better for Trump in the abstract than in reality, Jackson said. "Immigration, in reality, is complicated, messy and difficult."
• "The real question is going to be... does that level of support maintain or fragment as they confront the reality of what it means."

The other side: About one in 10 Americans — and close to 1 in 5 Republicans — said they'd support deporting immigrants who are in the country lawfully.

Context: Trump has said he would use the military to round up undocumented immigrants and would consider putting them into camps.

• Trump also has said he would deport American citizens if that means it would keep families together since he wanted to deport their undocumented parents or spouses.
• And he has indicated interest in deporting Haitian immigrants who currently have Temporary Protected Status.

The bottom line: To remove a sizable proportion of the estimated 11 million or more undocumented immigrants from the country, Trump would need not only broad but sustained public support.

Methodology: This Axios/Ipsos Poll was conducted Jan. 10-12, 2025, by Ipsos' KnowledgePanel®. This poll is based on a nationally representative probability sample of 1,025 U.S. adults age 18 or older.

• The margin of sampling error is ±3.2 percentage points at the 95% confidence level, for results based on the entire sample.