(CNN) There are few issues as contentious in international politics as the Israeli-Palestinian conflict.

But for the better part of the past two decades, the establishment wings of both the Republican and Democratic Party have largely been pro-Israel. Both parties have, at least in their party platforms, maintained pro-Israel positions, including calls to recognize Jerusalem as the Jewish nation's capital

While the Republican Party has become more pro-Israel recently, it's unclear whether the Democratic Party will be able to maintain a pro-Israel tilt.

Today, the Pew Research Center finds Democrats are less pro-Israel than they've been in decades. That drop has occurred in a period of just two years since 2016.

This year, 27% of Democrats said their sympathies lied with the Israel over the Palestinians in their conflict, while 25% said the Palestinians. The rest said both or neither. Just two years ago (when the Democrats adopted more pro-Palestinian positions in their plank), 43% of Democrats said their sympathies aligned with Israel compared with 29% who said the Palestinians.

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