Almost 1 in 5 Facebook users who shared fake news stories were Republicans over 65.

[sl8]

3. Study:

I believe this is the study the article refers to:
https://advances.sciencemag.org/content/5/1/eaau4586.full

Less than you think: Prevalence and predictors of fake news dissemination on Facebook

Andrew Guess1,*, Jonathan Nagler2 and Joshua Tucker2
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Science Advances 09 Jan 2019:
Vol. 5, no. 1, eaau4586
DOI: 10.1126/sciadv.aau4586

Abstract
So-called “fake news” has renewed concerns about the prevalence and effects of misinformation in political campaigns. Given the potential for widespread dissemination of this material, we examine the individual-level characteristics associated with sharing false articles during the 2016 U.S. presidential campaign. To do so, we uniquely link an original survey with respondents’ sharing activity as recorded in Facebook profile data. First and foremost, we find that sharing this content was a relatively rare activity. Conservatives were more likely to share articles from fake news domains, which in 2016 were largely pro-Trump in orientation, than liberals or moderates. We also find a strong age effect, which persists after controlling for partisanship and ideology: On average, users over 65 shared nearly seven times as many articles from fake news domains as the youngest age group.

INTRODUCTION
One of the most discussed phenomena in the aftermath of the 2016 U.S. presidential election was the spread and possible influence of “fake news”—false or misleading content intentionally dressed up to look like news articles, often for the purpose of generating ad revenue. Scholars and commentators have raised concerns about the implications of fake news for the quality of democratic discourse, as well as the prevalence of misinformation more generally (1). Some have gone so far as to assert that such content had a persuasive impact that could have affected the election outcome, although the best evidence suggests that these claims are farfetched (2). While evidence is growing on the prevalence (3), believability (2), and resistance to corrections (4, 5) of fake news during the 2016 campaign, less is known about the mechanisms behind its spread (6). Some of the earliest journalistic accounts of fake news highlighted its popularity on social media, especially Facebook (7). Visits to Facebook appear to be much more common than other platforms before visits to fake news articles in web consumption data, suggesting a powerful role for the social network (3), but what is the role of social transmission—in particular, social sharing—in the spread of this pernicious form of false political content? Here, we provide important new evidence complementing the small but growing body of literature on the fake news phenomenon.

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