No issue has defined Donald Trump's candidacy as has immigration. He announced his campaign last year by describing immigrants from Mexico as "rapists," frequently talked about violent crimes committed by undocumented immigrants on the stump and called for temporarily barring Muslims from entering the country.

When it comes to specific immigration policies, however, the Republican president-elect is at odds with many of his voters, who are surprisingly divided on the issue. Polls suggest that pluralities or even majorities of Trump's voters reject his proposal to deport all undocumented immigrants and instead favor eventual citizenship for those who are here illegally.

The data does not suggest that Trump's voters ignored his rhetoric on immigration. They do have more negative views of immigrants than the country as a whole. Their attraction to Trump's punitive positions on immigration, however, appears to be symbolic as opposed to substantive. When asked about specific policies, their views are more similar to those of other Americans.

Getting an accurate read on public opinion on immigration will be important for policymakers in the new administration. In Congress, many legislators in both parties continue to support eventual citizenship. If Trump's mandate with regard to immigration is weaker than it seems, it may prove more difficult for him to win over those lawmakers and to enact his agenda.

A poll conducted by The Washington Post and ABC News in September showed that just 30 percent of those supporting Trump and his running mate, Indiana Gov. Mike Pence, also favored deporting all undocumented immigrants who were here illegally. Sixty percent -- twice the share -- favored eventual citizenship.

Data from the Pew Research Center confirm this finding. Sixty percent of those supporting Trump said they believed people who are in the country illegally should be allowed to stay if they meet certain requirements. Just 32 percent said there should be an effort to deport them.

Interviews with voters as they exited the polls Tuesday suggest that Trump's supporters have more conservative views on immigration, but even in those polls, fully 50 percent supported eventual citizenship for undocumented immigrants. By comparison, 44 percent of Trump's supporters said they wanted everyone in the country illegally deported, according to the exit polls conducted on behalf of a consortium of T.V. news outlets and the Associated Press.

There are a couple of possible explanations for the discrepancy with the exit polls. It could be that those who in fact turned out at the polls to vote for Trump and Pence are somewhat more conservative on the issue of immigration.

Slight variations in the wording of the question could also explain the difference: For instance, while The Post asked voters whether "all" undocumented immigrants should have "a path to citizenship for those who pass background checks," the exit poll asked voters whether "most" immigrants here illegally should receive "a chance to apply for legal status." Without mentioning background checks and allowing for some undocumented to stay, the exit poll might have made the option of deportation appear more attractive.

The exit polls also suggest that immigration might not have been what motivated many of Trump's voters. Only 17 percent said it was the most important issue to them. More were concerned about the economy (46 percent) and terrorism (22 percent).

In any case, there is a clear disparity between between Trump's harsh words on immigrants and his supporters' positions.

The Post-ABC poll suggests a potential interpretation. In that poll, 72 percent of Trump's supporters said they approved "of the way Trump has been explaining his policy on how to handle undocumented immigrants." This figure suggests that his supporters like how Trump talked about the policies, even if they did not like the policy itself.

Perhaps they appreciated Trump's politically incorrect language, and they liked the fact that he acknowledged the discomfort with immigrants that many feel. A plurality of 43 percent of Trump's supporters told The Post and ABC News that that immigrants "mainly weaken American society," compared to 37 percent who said they feel that immigrants strength society.

As for the notion of actually deporting millions of undocumented immigrants, however, the bulk of Trump's supporters are skeptical, despite this discomfort.

Among the general population, mass deportation remains very unpopular. Just 15 percent of all respondents in the Post-ABC poll support deporting all undocumented immigrants, and 64 percent say immigrants mainly strengthen American society.

Emily Guskin contributed to this report. 

This post has been expanded with data from the Pew Research Center.

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