As the presidential race tightens, the first debate, set to take place on September 26, looms large. And while questions about each candidate's temperament and preparedness for office will surely come up, there is no doubt that the debate will also address what has become Donald Trump's signature issue, immigration.
Compared to Trump, Hillary Clinton has been relatively quiet on immigration. She has declared support for various policies, including comprehensive immigration reform, but has not held any signature events or speeches in the general election focusing on the issue.
Our research suggests that this is a mistake, since allowing Trump's negative rhetoric on immigration to dominate media coverage pushes public opinion in a more anti-immigrant direction. Clinton may worry that highlighting the issue will cost her votes with whites, but our findings suggest that she can seize the high ground on immigration in ways that are politically advantageous.
From her various statements so far, we know that Clinton would push for comprehensive immigration reform with a pathway to citizenship. If that is not achievable in the near term, she supports passing the DREAM Act and extending President Obama's executive actions on immigration, including those currently held up in federal court involving the implementation of Deferred Action for Parents of Americans and Legal Permanent Residents (or DAPA). And in an important contrast to Trump, Clinton also opposes the massive deportation of undocumented immigrants without a criminal record.
How might Clinton lay out her positions in a way that resonates not only with her core supporters, but also with undecided voters? Our recently published book on immigration framing and public opinion can offer some insights. Our research shows that public opinion is persuadable, even on an issue that is as highly charged as immigration. While the American public may have firm opinions of immigrants, they have much less stable opinions on particular policies that affect the undocumented population. Because of this, the ways in which policies are pitched to the public, more so than the policies themselves, can have important influences on opinion.
In fact, the public can appear to hold contradictory opinion on immigration policies when survey questions are asked in different ways. For example, in a Quinnipiac University Poll in 2012, the public had high levels of support for Arizona's SB 1070, which is a pro-deportation policy. Within the same poll, the public also showed high levels of support for Deferred Action for Childhood Arrivals (DACA). While this may be puzzling, the questions highlighted very different features of the immigration debate, the former on law and order, and the latter on children, which pushed opinion in different directions.
The key for Clinton will be to move away from general talk about immigration and to focus on particular dimensions of immigration policy that resonate well with the American public. There are three framing strategies on immigration that Clinton can count on. First, she needs to show that Trump's policies of mass deportation would harm the American economy.
Clinton also needs to get Americans to focus on the vast majority of immigrants who stand to benefit from immigration reform, rather than the small number of criminals who are currently evading law enforcement. Finally, Clinton has the opportunity to show her bipartisan appeal, by noting that many of her ideas and proposals on immigration draw support from Republican and independent voters alike.
On the first point, our research shows that novel economic arguments can be very effective in moving public opinion on immigration. In surveys, we find that highlighting how expensive it would be to deport all of the undocumented immigrants in the country cuts public support for deportations almost in half.
This could serve as an important counter-point to Trump's proposal for a massive deportation force. Novel economic frames also lead to further support for legalization, at least among some voters. For example, when we told survey respondents that immigrant legalization would substantially add money to the U.S. economy, support increased among Democrats. Such positive economic frames are not covered as extensively in the press, and could counter Trump's claims that immigrants take away jobs and use scarce public resources.
On the second strategy, Clinton needs voters to focus on the millions of children and law-abiding parents who are suffering from current policies, rather than the disproportionately small number of criminal aliens that Trump focuses on. Our research finds that support for policies like the DREAM Act and Deferred Action increase even further when people are told that many undocumented immigrants came to the U.S. as young children.
We also find that public support for legalization and opposition to deportations increase substantially the longer law-abiding immigrants have been in the U.S. On average, people are somewhat opposed to deporting law-abiding immigrants who have lived in the U.S. for as little as five years, and opposition becomes even stronger for longer-term immigrants.
Finally, Clinton should attach whatever claims she can to conservative sources. We find that frames coming from an unexpected source, especially on the right, make individuals more supportive of comprehensive immigration reform with a path to citizenship, and more opposed to deportations. For example, she can point out that the DREAM Act started as a bi-partisan bill. She can also reference Republicans, including some of the presidential contenders, who have supported attempts at legalization, such as Marco Rubio.
More aggressively countering the negative frames about immigrants from the Trump camp will be important for Clinton in two ways. First, it will lead to shifts in public opinion on various policies related to the undocumented population. This may in turn reduce support for Trump, especially since it is one of his signature issues.
Second, while Trump's negative rhetoric is likely to mobilize Latinos in the election, more forcefully combating his rhetoric may also further energize the community, especially the activists who are key to mobilization efforts. Both persuasion and mobilization will be important in a race that has gotten tighter.
The first presidential debate is expected to draw a wide audience, maybe even bigger than the Super Bowl. Hillary Clinton will therefore want to use every opportunity she can to re-shape the narrative around immigration. This will not only further mobilize her supporters, but will be an important way to gain inroads to the many voters in the middle who have less firmly held opinions on specific immigration policies, and have up to this point in the election been primarily exposed to the negative rhetoric coming from Donald Trump.
Commentary by Karthick Ramakrishnan, Jennifer Merolla and Chris Haynes. Ramakrishnan and Merolla are professors of political science at the University of California at Riverside. Chris Haynes is assistant professor of political science at University of New Haven. Together they are authors of Framing Immigrants,a new book from Russell Sage Foundation. Follow Ramakrishnan on Twitter @karthickr.
For more insight from CNBC contributors, follow @CNBCopinion on Twitter.
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