Republican presidential candidates, from left, former Pennsylvania senator Rick Santorum, former New York governor George Pataki, Sen. Rand Paul of Kentucky, former Arkansas governor Mike Huckabee, Sen. Marco Rubio of Florida, Sen. Ted Cruz of Texas, retired neurosurgeon Ben Carson, businessman Donald Trump, former Florida governor Jeb Bush, Wisconsin Gov. Scott Walker, businesswoman Carly Fiorina, Ohio Gov. John Kasich, and New Jersey Gov. Chris Christie take the stage during the CNN Republican presidential debate at the Ronald Reagan Presidential Library and Museum on Wednesday, Sept. 16, 2015, in Simi Valley, Calif. (AP Photo/Chris Carlson)

The Republican primary debates have been emphasizing foreign policy, and for good reason.

According to the 2015 Chicago Council Survey of the American public released last week, Republicans are more likely than Democrats to see a dangerous world and to prioritize maintaining U.S. military superiority and using force to achieve U.S. goals. But as the Republican debates demonstrated recently, not all GOP primary candidates sing this tune.

So which candidates best represent Republican voters — and Americans in general — on the foreign policy topics being discussed in the Republican primary debates?

In some ways, the Republican candidates help illustrate the full array of the GOP public’s preferences on foreign policy. The survey reveals interesting differences between those Americans who describe themselves as either “strong” and “weak” GOP supporters, especially when it comes to immigration, dealing with Iran, lifting the embargo against Cuba, and climate.

Immigration

Start with immigration, which moderator of the second GOP candidates debate Jake Tapper called the most “combustible” topic of the campaign so far. The candidates were ready to crack down on those in the country without papers, albeit in different ways: Donald Trump wants to build a wall; Chris Christie wants to use everything from drones to mandatory fingerprinting for all visa holders to hold them accountable; Ben Carson wants to turn off “the spigot that dispenses all the goodies” and to allow in new immigrants primarily as guest workers to the agricultural sphere; Jeb Bush called all this impractical and costly, and championed a “comprehensive, conservative” approach.

Republican voters show a similar spread of opinions in the Chicago Council Survey results.

Strong Republicans tend to view deportation as the best way to address illegal immigration (53 percent vs. 32 percent who say that illegal immigrants should be allowed to stay in the United States with a path to citizenship). Weak Republicans are more divided and in fact more open toward a path to citizenship than GOP candidates seem willing to admit: similar proportions of weak Republicans choose deportation (38 percent) vs. allowing unauthorized workers to stay in country with a path to citizenship (42 percent).


The Iran nuclear deal

During last week’s debate, Ted Cruz, Marco Rubio and others reiterated their criticism of the Iran agreement, while John Kasich and Rand Paul were inclined to give the deal a chance, without approving the deal outright.

The Chicago Council Survey was conducted before the agreement with Iran was finalized, in May and June 2015. At that time, 59 percent of those polled supported the outlines of a deal with Iran; of Republicans, only 46 percent supported it while 51 percent opposed it. Should Iran commit a major violation of a nuclear deal, only among Republicans did a majority support the use of U.S. forces to destroy Iran’s nuclear facilities.

But within the Republican electorate, there were a range of opinions. A majority of “weak” GOP supporters — 55 percent — favored the deal, compared with only 37 percent of strong Republicans.

Support for using U.S. troops to destroy Iran’s nuclear facilities was substantially higher among strong Republicans, at 59 percent, than weak Republicans, at only 47 percent.


Climate change

Tapper introduced the issue of climate change by paraphrasing former secretary of state George Shultz, who noted that when the scientific community issued warnings about shrinking ozone layers, Ronald Reagan asked industry skeptics to come up with a plan as an “insurance policy” in case the scientists were right.

Both Rubio and Christie rejected what they called a “left wing” approach to climate change that could hurt business, even when Tapper reminded them that George Shultz was not exactly a left wing voice.

Of all the foreign policy issues presented in the 2015 Chicago Council Survey, climate change is the most polarizing for the American public. Twice as many self-described Democrats as Republicans consider climate change a critical threat with a difference of about 40 percentage points. But there are also interesting internal divisions among Republicans. Although 59 percent of strong Republicans question whether climate change is actually a problem, a majority of weak Republicans — 55 percent — consider climate change a real problem that should be addressed through gradual action.


U.S. relations with Cuba

When the Obama administration announced the restoration of diplomatic relations with Cuba, several Republicans criticized the policy, including Bush, Cruz and Rubio. The Republican electorate shows more variety than the candidates: Six in 10 Republicans support lifting the economic embargo against Cuba, with weak Republicans much more in favor than strong Republicans, 67 percent to 51 percent.

In other words, factionalism is alive within the GOP. That may not be good for the ultimate nominee. Immigration is the clearest example. While Trump and others have tapped into a segment of the GOP public’s fear of undocumented immigration, among Republican elites only a minority of political, government, business and academic leaders see undocumented immigration as a threat, according to the Chicago Council’s 2014 leaders survey. So far, this minority has dominated the Republican debate and explains why candidates who were previously immigration moderates are feeling the pressure to move to the right.

Candidates searching for voters among the base should keep their eye on the bigger prize. Deportation and walls are not common ground for the majority of Americans who will vote for president in 2016, who instead favor a path to citizenship.

Dina Smeltz is a senior fellow of public opinion and foreign policy at The Chicago Council on Global Affairs. She has more than 20 years of experience conducting surveys in the United States.