Gallup's annual World Affairs survey shows that only 48 percent of those identifying as Democrats sympathize more with Israelis in tensions in the Mideast than with Palestinians. In contrast, 83 percent of Republicans side with Israelis. The figure for all Americans is 62 percent.

As that graph of the trend by party shows, that summary masks some nuance. That 48 percent of Democrats is actually up significantly since the mid-1990s -- as is the figure for Republicans.

Over the past 12 months, though, there's been a drop of support for Israelis of about ten points by Democrats, a plunge that rivals the decline seen among all parties after a boost of support during the first Gulf War. Gallup suggests that timing may have played a role. The survey was conducted earlier this month, as the debate over Israeli prime minister Benjamin Netanyahu's upcoming speech to Congress began to heat up. The speech and the invitation that prompted it have been criticized in the United States and in Israel as injecting partisan politics into the relationship between the two countries. Gallup's survey suggests that might be true.

The graph above also masks Americans' overall support of Israel. Seventy percent of Americans rate Israel favorably, down a tick from the 72 percent expressed in 2014, but nothing substantial. That trend has also been consistently upward since the 1990s.