It is a fight that Michael Phillips knew all along would not be easy.

He told WFAA that his decision to start a campaign to bring down the Confederate monuments really started after the 2015 Charleston church shooting, in which Dylann Roof was convicted of shooting and killing nine black church-goers.

What Phillips and his wife, Betsy, did not envision was that the campaign would take off.

"We never really had an idea that so many people would feel this was a clarion call for them," said Betsy Friauf.

But leading any cause means exposure. Exposure comes at rallies and even in media interviews. Michael told WFAA that he knew, to a certain extent, that the campaign would require him to go out of his comfort zones.

He did not expect what came his way earlier this week in the way of an email.

"The sentiments are so ugly and it shows in a sad way how little ground we've covered," he said.

Phillips said he is used to getting threats, especially on social media, but death threats not so much. It would prompt the Collin College history professor to call Plano Police on Tuesday.

"When I go outdoors I look to make sure our tires haven't been slashed but that is about the extent of my vigilance," said Friauf.

The threats even prompted both Phillips and Friauf to tell their employers. The email started with, "Hey N----lover!"

It goes on to say, "If I was you, I would be looking over my shoulder to see who's coming up behind me. They may not be friendly."

The email also reads, "if you keep yelling for their removal you're liable to make someone mad and they will take you out."

Phillips told WFAA he has no right to be intimidated.

"There are millions of Americans who face mortal danger every time they step out the door because of their skin color or because of their religious faith or because of their orientation or gender identity," he said.

Both said their campaign will continue on. Phillips said an officer told them to stay vigilant and keep all doors and windows closed and locked at all times.