There are two errors there.
First, that is not a hyphen in the original Wikipedia article. It’s intended to be a dash, but even a dash there would be used improperly. It should be simply a comma.
Second, the word “were” is the wrong word. It should be “where.” And third, a verb was omitted later in the sentence. (This whole mess is an example of poor writing in Wikipedia.)
Now, how does this sentence read to you? ~~> In February 2014, New Jersey State Senate President Stephen Sweeney argued that Jersey City, among other distressed cities, could benefit from a casino, where construction of one outside of Atlantic City eventually [was] permitted by New Jersey.
In February 2014, New Jersey State Senate President Stephen Sweeney argued that Jersey City, among other distressed cities, could benefit from a casino-were construction of one outside of Atlantic City eventually permitted by New Jersey.
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What is "a casino-were construction"?
2 answers
Should read: There are three errors there.