Brown, a Republican, and Warren, a Democrat, have barely mentioned foreign policy on the campaign stump. But in written responses to questions from the Globe about Syria, Russia, Iran, the Israeli-Palestinian conflict, and other areas, Brown and Warren provided a broader picture of their views on some of the thorniest foreign policy questions facing the United States. The winning candidate will, as a US senator, be in a position to help shape policy and act on treaties and declarations of war.

The candidates’ responses revealed several key areas of disagreement, and Brown’s ­answers were striking for the way he distanced himself from Republican presidential nominee Mitt Romney’s views and aligned himself with President Obama. Brown has also been distancing himself from ­Romney on domestic issues, reflecting the challenge he faces as a Republican running in a traditionally Democratic state.

Brown and Warren agreed, perhaps to a surprising extent, on many areas, and their responses often restated longstanding American foreign policy rather than offer their own policy prescriptions. Their caution suggested they do not see any political advantage in staking out bold stances on foreign policy at a time when voters are more focused on economic issues.

Brown, who serves on the Armed Services Committee, was at times more substantive in his answers than Warren, a foreign policy neophyte.

But “neither is taking crazy positions,” said Leslie H. Gelb, a former president of the Council on Foreign Relations who reviewed the responses from Brown and Warren. Both candidates embrace “pretty much centrist and White House policies.”

One of the key areas of disagreement between Brown and Warren was over Syria, which is in the throes of a bloody civil war that began 17 months ago when President Bashar Assad cracked down on protesters.

Since then, street battles and air attacks have left an estimated 27,000 dead and provoked a humanitarian crisis for hundreds of thousands of civilians. Brown said he wants to go beyond the nonmilitary and humanitarian aid the Obama administration is currently providing the rebels.

“I also believe it is appropriate to identify moderate ­elements within the opposition and provide them with weapons so they can fight back against Assad and the Syrian army,” Brown wrote.

“With so many innocent Syrians being slaughtered ­every day, we should do what we can to level the playing field,” he wrote. “However, I do not at this time support sending in US ground forces or the imposition of a no-fly zone.”

Senator John McCain, ­Republican of Arizona, and former secretary of state ­Condoleezza Rice have also urged the United States to arm moderate rebels. Many foreign policy specialists say the idea is good in theory, but has not been feasible because no one knows who those moderates are.

“Who can be against helping the good guys, and at no cost to ourselves?” said ­Michael Mandelbaum, director of the American Foreign Policy Program at Johns Hopkins University. “The question is, can we identify the good guys, and avoid the cost and, even if we can, is it going to be of any help?”

Warren said she supports nonmilitary aid to the rebels but hedged on arming them and instituting a no-fly zone, saying they “must be carefully considered.”

“We cannot take such ­action without a clear sense of what we are getting into and what we need to do to succeed,” she wrote. “Because lethal assistance can have complex and unintended consequences, we should not act unless we are confident that we can do more good than harm and that we have a clear plan and achievable goals.”

Another area of disagreement between Brown and Warren centers on the Israeli-Palestinian conflict. While both said they support the establishment of a Palestinian state alongside Israel, Brown said a two-state solution must affirm “Jerusalem as the undivided capital of the state of ­Israel,” among other conditions.