It turns out that the answer is probably not, but not yes or no, either. Fairleigh Dickinson University released a poll and some analysis on popular conspiracy theories yesterday and the aftermath today was ugly. Salon, Think Progress, and presumably other sites jumped the gun by declaring that more than two-in-three Republicans are birthers, but the poll never asked that question.
In fact it didn't ask any questions at all, it made statements and then asked people how they felt about them. Two statements about voter fraud in 2008 and 2012 were alright, as far as the way they were worded, so I won't talk about them here. The other two were worded quite poorly.
Statement #3: President Bush know about the 9/11 attacks before they happened.
If you think this question is about "truthers", you'd be wrong. That may have been the intent, but that's not what the statement says. This statement could easily refer (and apply) to the Presidential Daily Briefing that President Bush received before 9/11 warning that Osama bin Laden was determined to strike inside the United States, possibly using civilian aircraft as weapons against buildings. It's true that President Bush was aware of those warnings, but that's not the same thing as knowing about the actual attacks that were coming. Regardless of where you stand on the truther theory, this question is too vague to be useful.
Statement #4: President Obama is hiding important information about his background and early life.
This statement is even worse, given the sheer number of conspiracy theories that have developed since 2008. It could refer to Obama's citizenship, but it could also apply to his school records, medical records, associations with controversial figures like William Ayers, drug use or abuse, or one of dozens more.
That's probably why you'll find very few birthers in the Democratic Party, yet 44% of Democrats said that statement #4 was either true, or somewhat true. (That's another criticism: Fairleigh gave "true" and "somewhat true" as acceptable answers, but then combined them in their results which can be misleading.)
There aren't very many good conclusions that can be salvaged from this flawed poll, but I'll try.
Lots of gullible Americans - 64% of Republicans and 44% of Democrats find at least one conspiracy theory about President Obama's history to be at least somewhat likely. But what if only 10-20% of each believe statement #4 is "true", and all the rest only think that it's "somewhat true"? That changes everything.
Clear racial divide - Whites are divided over whether or not President Obama is hiding something, 42-47. Blacks are far more resolute that he's not hiding anything, 69-17.
High information voters - Fairleigh asked four test questions about current events to gauge how informed their respondents were. I'd love to see this done in every poll in the future. As you might have guessed (but now we have some quantitative evidence), the propensity for believing conspiracy theories correlates strongly with ignorance of current events.
The questions were: who is the Secretary of State, who controls the House majority, is unemployment higher/the same/lower than when President Obama first took office, and which country are drone strikes on terrorists mos concentrated. The first two questions should be easy to answer for anyone who is minimally engaged in politics, but the last two are problematic.
The university actually appears to have a significant error in their report in regards to unemployment. One part of the report says that the question was "Is unemployment higher, lower, or the same as it was when President Obama first took office in 2009?".
But the results area says "As far as you know, has unemployment increased, decreased, or stayed the same over the past twelve months?"
The correct answers are that unemployment has dropped 0.7 points in the last 12 months, but was the same in December of 2012 as it was in January of 2009, 7.8%. If the pollster can't even get this right, how can you expect Americans too?
Anyway, the results are much like you'd expect. High information voters who got all four questions right were the least likely to believe that the President is hiding things from his past, 22-74. Low information voters were the most likely, 41-34. But that is not the case with all conspiracy theories:
President Bush's supporters committed fraud in Ohio in 2004
4 correct: 27-49
3 correct: 18-52 (not true high)
2 correct: 24-41
1 correct: 14-34 (true low)
0 correct: 38-22
President Obama's supporters committed fraud in 2012
4 correct: 11-75 (not true high, true low)
3 correct: 24-58
2 correct: 20-53
1 correct: 16-46
0 correct: 22-33
President Bush knew about 9/11 beforehand
4 correct: 13-76 (not true high, true low)
3 correct: 22-67
2 correct: 27-50
1 correct: 27-45
0 correct: 42-28
President Obama is hiding information about his past
4 correct: 22-74 (not true high, true low)
3 correct: 37-52
2 correct: 40-47
1 correct: 38-36
0 correct: 41-34
For whatever reason, being well informed correlates very well with not believing any of these conspiracy theories except that Republican voters stole the 2004 election by cheating in Ohio.
I think we could all use a good poll testing many popular conspiracy theories, but this poll doesn't do that, so it's just not that useful.