It's the old folks who don't get their information from the internet who are okay with giving up their privacy for security. IMHO they're a lost cause because the mainstream media's stranglehold on them is far too strong to ever break.
Look at the 18-29 demographic in the poll-- neck and neck, and likely to be heavily swayed toward sacrificing privacy by the most recent terrorist attacks in Paris. There can be a real debate with these people, informed by what Snowden brought out.
These are the people who grew up with the internet. They're probably the most likely to have heard of evil government dissent-squashing programs like COINTELPRO and its modern successor, JTRIG. I am always beating this drum to anyone who will listen (and unfortunately I am probably preaching to the choir here), but here's a few thoughts on why trading privacy for security is a terrible decision:
1. Privacy "traded" for security is usually just taken by the government using a flimsy excuse without any input from the public.
2. This stolen privacy is never given back, even when the alleged threat passes.
3. The information gained from stolen privacy will be used for things other than the alleged purpose-- the timely example here is the NSA's parallel construction (legal system circumvention) used to make drug arrests.
4. The information gained from stolen privacy will be used to crush nonviolent dissenters (JTRIG, COINTELPRO, many other programs).
5. The information gained from stolen privacy will be handed off to third parties for gain(corporations, friendly governments)-- Palantir, Google, military contractors, whatever else.
6. The information gained from stolen privacy won't be able to stop whatever it claims it will help in stopping--the perfect example here is the Boston bombing, in which surveillance of the two perpetrators didn't prevent the attack.
7. The information gained from stolen privacy will certainly create a chilling effect which will prevent people from speaking about and eventually thinking about topics they think will get them into trouble-- you see this all the time already with people grumbling about how they are probably "on the list".
I am going to be bold and say that people who support trading privacy for security don't understand the issue, have been systematically misled, desire totalitarianism, or have a monetary incentive.