Pew finds an increasingly large partisan gap in sympathy for Israel:
I have long thought that the framing of this question is guaranteed to give a misleading result, since it asks respondents which side in the conflict they sympathize with more. Respondents are rarely asked whether they think the U.S. should be actively backing one side or the other. When they are asked this, Americans overwhelmingly favor neutrality, and this is obviously not the position that the U.S. takes in the conflict. The sympathy question greatly overstates the degree of American support for Israel.
Considering how uniformly and uncritically “pro-Israel” our politicians tend to be, it is remarkable that only 51% say that they sympathize more with Israel in the conflict. If popular support for Israel were as great and widespread as is commonly claimed, one would expect it to be much higher. The partisan gap is interesting in that it comes entirely from a huge increase in Republicans’ sympathy for Israel over the last twenty years or so. Sympathy among independents and Democrats is identical to what it was in 1978, but among Republicans it has shot up twenty-four points in the same period.
The influx of evangelicals into the Republican coalition may account for some of that, but it can’t explain all of it. This large increase is almost certainly driven in large part by the relentlessly positive coverage given to Israel in conservative media and the near-total “pro-Israel” uniformity among conservative pundits. Not only have Republicans been constantly propagandized on this subject in one direction, but being “pro-Israel” in a particularly hawkish way has become for all intents and purposes an important litmus test for being a “good” Republican in the eyes of party elites. For the most part, rank-and-file Republicans go along with this, or at least do not strongly object to it. I suspect that this isn’t because most of them have a particularly strong attachment to or enthusiasm for Israel, but because this is something that party leaders and pundits say that Republicans are supposed to believe.
If we look at all non-Republican political groups, we find that sympathy for Israel is not a majority view with any of them:
The partisan gap is also a generational one. Older respondents are much more likely than younger ones to sympathize with Israelis. To some extent, that is a measure of how much less conservative and Republican most younger Americans are, but it is telling that the Americans that have come of age over the last thirty years are much less likely to be sympathetic. For Americans under 50, the Israel that they have seen on the news is the one that invaded and occupied Lebanon, consistently expanded its occupation of Palestinian territories, bombed Lebanon and Gaza more recently, and openly talks about doing the same to Iran. Younger generations of Americans see fewer reasons to sympathize with Israel than their parents and grandparents do, and Israeli governments are giving them more reasons not to, and that suggests that American sympathy for Israel is going to keep dropping in the years to come while Republicans will be increasingly identified–to their gradual political detriment–as the “pro-Israel” hawkish party.