The messages, too graphic to show or say in their entirety, call her disparaging words, including the n-word, telling her to die or leave the borough.
Coffee said someone taped the messages to the front doors of her home. Another note was left inside an enclosed porch, which meant someone walked through a door to get inside that area.
"It bothered me, it bothered me because the night before, my daughter and I were sleeping on the couch," said Coffee.
"I didn't hear anything," said Coffee.
The Collingdale police are investigating the incident.
Detectives took the messages written in black marker into evidence and searched nearby properties for cameras to identify the suspect.
Collingdale Police Chief Kenneth Felker told Action News the case was turned over to the district attorney's special prosecution unit.
Coffee said the harassment started on social media during the campaign, but she never expected it to escalate.
"Maybe they just wanted to scare me, or intimidate me," said Coffee.
But Coffee said she is not intimidated.
"I understand that people are very passionate for what they believe in, I get that. I get it. But your passion should spew over in another way, instead of such a derogatory way," she said. "I'm not going anywhere. The people have elected me to represent Collingdale. And for the people who didn't, I would hope that we could still come together."