What percentage of US Christians are Dispensationalists? What percentage of US Christians are dispensationalists?  I think it has a serious impact on American policy in the Middle East. 


  Dispensationalism is a religious interpretive system and metanarrative
  for the Bible. It considers Biblical history as divided by God into
  dispensations, defined periods or ages to which God has allotted
  distinctive administrative principles. Source
I can't find any surveys that asked Americans about dispensational belief directly. Dispensational theology is mainstream in evangelical Protestant circles, though being an evangelical doesn't necessarily mean one believes in premillenial dispensationalism. Many people probably do not have fixed theological positions, and cannot fairly be said either to believe or disbelieve dispensationalist theories. There are also theologically conservative Protestant churches that might not be called "evangelical" that hold to dispensationalism.  I would guess that the number of evangelicals in the US provides an upper bound on the number of dispensationalists. According to the Pew Research Center, as of 2014 about 25% of Americans are evangelical Protestants. 

More directly relevant to the reasoning behind the question, a Pew Research Center study from 2003 reports that 36% of Americans (of any religion) say that Israel fulfills Biblical prophecies about the Second Coming. I don't see why you would have to believe in dispensational eschatology to believe that, though. For example, 25% of Catholics said they believed Israel fulfills Biblical prophecies, and official Catholic doctrine is not dispensationalist. Of course, ordinary Catholics may not conform to official doctrine, and I'm pretty sure the official Catholic doctrine is that the state of Israel has no religious significance. 

That study also reports that 63% of self-identified evangelicals believe Israel fulfills Biblical prophecies. Again, not all of them are necessarily dispensationalists. One could also, in theory, be a dispensationalist and not think the current state of Israel is the fulfillment of prophecy, but the dominant dispensationalist view says it is. If we assume that nearly all evangelicals who think Israel fulfills prophecy are dispensationalists, and that those who think it doesn't are not, and we assume that 63% of evangelicals still think Israel fulfills Biblical prophecy in 2014, then we might take 63% of 25% = 16% of Americans as a lower bound on the number of dispensationalists.  Since about 80% of Americans are Christian, that would be about 20% of Christians. But I've made some pretty suspect assumptions here. My guess is that between 15% and 25% of Americans are not not dispensationalists; that is, their beliefs are basically consistent with dispensationalism, even if they don't have articulated eschatological beliefs.

One addendum: the 80% of Americans who are Christians excludes people of no religion, who mostly come from Christian families.  Only about 5% of Americans identify with a non-Christian religion.