We might not have booth capturing in the United States, but people have been influenced to vote one way or another over the years in various ways. Some tactics are subtle, while others are not.
For example, my grandfather was a state employee. Prior to elections, he was told to "vote right" or forget about having a job. The implication was that his private ballot wasn't so private and that his vote would be known by the party that was in power at the time.
Could a political party get access to how someone voted? Maybe and maybe not. However, the threat of losing a job is severe enough to make someone comply. The point, of course, is that booth capturing is obvious but threats such as the one my grandfather had to put up with are not.
There are other examples of voter intimidation. Things have gotten better over the years, but local election commissions should remain vigilant to make sure that the right to vote is protected.