The 2016 presidential primaries have upended a wide variety of assumptions about the rules of American politics, and what the traffic will bear. One of these areas is the Israeli-Palestinian conflict.

American political debate around the issue of Israel and Palestine has often been a highly emotional one, constrained within very tight rhetorical parameters. Over the past decade, the terms of this debate have been shifting slowly, but steadily. Whereas in previous years, questioning America’s relationship with Israel was unthinkable for a U.S. presidential hopeful, this year’s campaign has witnessed a widening of the space in which candidates can debate U.S. policy toward Israel-Palestine.

The creation in 2008 of the “pro-Israel, pro-peace” lobby group J Street, as a more liberal counterweight to the conservative-leaning American Israel Public Affairs Committee (AIPAC), was a major indicator of a shift in ‘acceptable’ political discussion on Israel. The very public tensions between President Barack Obama and Prime Minister Benjamin Netanyahu over the past few years further extended the parameters within which American politicians could question, and criticize, Israeli policies.

The ground shifted perceptibly during the 2015 debate over the P5+1-Iran nuclear agreement, particularly when Netanyahu surprised the White House with the announcement of a speech to Congress, agreed upon in secret with House Speaker John Boehner, against the deal. Coming as it did after Netanyahu’s stiff-arming of U.S. peace efforts, this clear breach of protocol, in an unprecedented effort to undermine the president’s foreign policy agenda in coordination with the president’s partisan critics, provoked a sharp reaction from numerous Democrats, many of whom refused to attend Netanyahu’s speech.

Moving into the 2016 primary season, polls had shown for some years that a growing divide on the issue of Israel-Palestine, with Democrats, particularly liberal Democrats, identifying less strongly with Israel, and more supportive of an even-handed U.S. approach to the conflict. A Gallup poll showed less than half of Democrats professing support for Israel over the Palestinians, a 10-point drop from the previous year. A found that, while a majority of voters still favor Israel, liberal Democrats supported the Palestinians (40 percent) over Israelis (30 percent).

This was the environment into which presidential candidate Senator Bernie Sanders made a series of forays. While his campaign had focused almost exclusively on issues of economic inequality and corporate influence on politics, his —which he had asked to deliver to AIPAC’s annual policy conference via video, a request they denied, despite having allowed past candidates to do the same—delved deeply into the Israeli-Palestinian issue. Noting that he was “probably the only candidate for president who has personal ties to Israel,”—he lived on a kibbutz for several months in the 1960s—Sanders nonetheless spoke up strongly for Palestinian rights and dignity, calling for an end to the occupation and the Gaza blockade.

Sanders sharpened this line of argument in a mid-April debate with his opponent, Secretary of State Hillary Clinton, in Brooklyn on the eve of the New York primary election. “I read Secretary Clinton’s speech before AIPAC. I heard virtually no discussion at all about the needs of the Palestinian people,” Sanders . “Of course Israel has a right to defend itself, but long-term, there will never be peace in that region, unless the United States plays an even-handed role, trying to bring people together and recognizing the serious problems that exist among the Palestinian people ... There comes a time when, if we pursue justice and peace, we are going to have to say that Netanyahu is not right all of the time.”

In May, for the Democratic National Convention’s platform drafting committee, which included a number of pro-Palestinian voices, indicating that the Sanders camp would seek to have the candidate’s views on a more ‘even-handed’ policy toward Israel-Palestine reflected in the party platform.

Meanwhile, in the Republican primary, a different but equally significant shift took place. Speaking at a town hall event before the South Carolina primary in February, frontrunner “neutral” between Israelis and Palestinians, a position regarded by many as heresy in a party that has grown extremely pro-Israel in recent years. But not only did Trump go on to win the South Carolina primary, he won a plurality (37 percent) , a feat he went on to repeat in several other contests. Conservative Christian evangelicals had long been assumed to be the strongest pro-Israel faction within the Republican party; at the very least, the primary results showed that, whatever their personal views, the issue of Israel didn’t rise to the level importance of denying a candidate their vote over it.

This leads to another potential causal factor that is resulting in more freedom for a U.S. politician to reassess America’s policy toward Israel and Palestine—the conflict no longer factors as a major priority for American voters. Traditional constituent voting groups that were relied upon to ensure a robust U.S. commitment to Israel, such as conservative Christian evangelicals and even liberal American Jews, have either prioritized other issues, or become weary of the seemingly endless Israeli-Palestinian conflict and therefore less inclined to energetically oppose new approaches. There’s also the fact that, thanks to changes in the media environment and the hard work of human rights groups in publicizing the reality on the ground, more Americans, particularly liberal Americans, have become aware of the ways in which Israeli policies of occupation and settlement cannot be reconciled their own deeply held values.

These results shouldn’t actually be so surprising. As reported in the Washington Post’s , surveys over many years show that, while larger numbers of Americans see Israel more favorably that Palestinians, Americans also generally favor the U.S. playing an even-handed, neutral role in brokering peace between the two sides. Polls conducted by the since 2002 have consistently found that “solid majorities of Democrats and independents and about half or more of Republicans repeatedly endorsed keeping a nonaligned U.S. role” in the Israeli-Palestinian conflict.

Preferences as expressed to pollsters are, of course, only part of the story. There’s also the question of intensity, of how high a respondent places that preference in their list of priorities, and how much time and effort they’re willing to commit to the issue beyond the voting booth. At the very least, however, the 2016 primaries have demonstrated that American leaders have considerably more political space to move on the issue of Israel-Palestine than has been long assumed.