Following their debate at a Yonkers television station on Tuesday evening, the Republican candidate for Westchester County District Attorney, Daniel Schorr, approached the Democratic candidate, incumbent Janet DiFiore, in the station’s parking lot to shake hands. Both Ms. DiFiore and her husband refused, Mr. Schorr said.

That encounter likely marks the last meeting between Mr. Schorr and Ms. DiFiore before Tuesday’s general election, as well as the peak in what has become an unusually contentious campaign.