Republicans sympathize with Israel in its conflict with Palestinians increasingly more strongly than Democrats do, according to a new Pew Research Center survey, opening up the widest partisan gap on American opinion on Israel since available polling in the late 1970s.

In a survey taken July 8-14, as Israel took military action in Gaza to protect its civilians against a barrage of rockets being launched by Palestinian terrorists, 51 percent of American respondents said they sympathized more with Israel than with the Palestinians, compared with 14 percent who sided more with the Palestinians.

But the partisan breakdown was stark. Though 73 percent of Republicans said they sympathized more with Israel, just 44 percent of Democrats felt that way. According to Pew, "dating back to the late 1970s, the partisan gap in Mideast sympathies has never been wider."

Among ideological groups, conservative Republicans sympathized with Israel over Palestinians by a 77-percent to 4-percent margin. In contrast, just 39 percent of liberal Democrats said they sympathized with Israel, compared with 21 percent who said they sympathized more with Palestinians.

The widening partisan gap is difficult news for the American Israel Public Affairs Committee*, a lobbying group that attempts to preserve the strong relationship between Israel and the United States by making support for Israel into a bipartisan issue.

But as conservative Republicans continue to push the party into an increasingly pro-Israel direction, liberals who believe that U.S. policy is too reflexively supportive of Israel and too unsympathetic to Palestinians are gaining influence within the Democratic Party.

The intense pro-Israel sentiment among conservatives also explains why potential 2016 presidential candidate Sen. Rand Paul, R-Ky., in a break with his father, has tried to frame his non-interventionist views as being pro-Israel, proposing a "Stand With Israel Act" to cut off aid to the Palestinians. If Paul were to give the impression that he sides with the Palestinians, he'd be allying himself with fewer than one in 20 conservatives.

Some political reporters like to talk about the "Sheldon Adelson primary" -- of Republican candidates seeking the approval of the pro-Israel casino magnate. As the Pew poll shows, however, the whole idea of of an "Adelson primary" is a sloppy description of what's happening within the GOP. In reality, support for Israel among Republican primary voters is broad and deep. A 77-percent to 4-percent issue among predominantly Christian conservatives is not representative of the party platform being overtaken by a small cabal of Jews. No Republican has a chance at the nomination if he or she is perceived as anything but a staunch supporter of Israel, and this goes far beyond Adelson.

* Disclosure: In 2008, the author took a trip to Israel funded by the AIPAC-linked American Israel Education Foundation.