I know because, as a resident in NJ's 5th district, I was one of the harassed recipients. The intended victim was Democratic candidate, Dr.Anne Sumers; and just like today, the robocalls fooled some people into believing that it was
she, and not Scott Garrett, who was behind them. The
Bergen Record wrote a short article on the matter, quoting Garrett's campaign as saying "we don't know who's behind them", a dubious claim considering his campaigns had been heavily funded by The Club For Growth, a renowned middle-man for GOP dirty tricks.
Earlier this year, I discovered that the incident was briefly mentioned in an obscure paper, later published online, written by a moderate Republican (ie., not someone happy with the current batch of Republicans), Tanya Melich:
http://www.iwpr.org/pdf/Melich_Tanya.pdf The most aggressive assault against her came four days before the election when nearly round-the-clock robo-calls were made into Bergen county Democratic and independent voter households. The caller was an unidentified woman who would say in a menacing voice to the person who picked up the phone, “I want you to know something about Anne Sumers” and then would quote one of the accusations made previously by the Garrett campaign or his independent committee supporters. Some households received as many as seven calls in one day. Many angrily telephoned the Sumers campaign and told it to stop harassing them. Some said they had planned to vote for Sumers, but the calls had turned them off. They said they would not be voting for either candidate.
The Garrett campaign claimed they had nothing to do with these calls. The Sumers campaign never found out who sponsored them or the name of the person calling. These robo-calls had the desired effect for Garrett‹they diminished the vote for Sumers.
Apparently, what happened in NJ four years ago was a dry run for what's happening nationally today.