University President Kent Fuchs tried to block Spencer's appearance, but he backed down in the face of a threatened lawsuit.
Saying there was an "imminent" threat of a potential emergency as a result, Scott explained that the emergency declaration will ensure that security forces have all the necessary resources at their disposition.
Spencer, the president of the white nationalist group National Policy Institute, is expected to deliver his views on Thursday afternoon at the university, and officials are wary that the incident could turn violent.
Spencer was involved in and spoke at a white nationalist rally in Charlottesville, Virginia in August that triggered a weekend of clashes.
The order allows state, county, and local agencies to coordinate their resources more quickly and freely before and during the rally in Gainesville and activates the Florida National Guard.
Prior to the declaration of a state of emergency, the University of Florida had already planned on spending $500,000 for extra security at the controversial event. I think it will be a good event.More news: Cow on the Loose in Prospect Park, Police Say
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The university will recoup $10,564 from Spencer's National Police Institute for the two-hour rental of the Phillips Center for the Performing Arts.
Following a press conference Monday morning, protesters marched from the Plaza of the Americas to the doors of the University of Florida's administrative building, Tigert Hall, to voice their wants and concerns.
However, we have zero tolerance for violence and public safety is always our number one priority. "That was basically a means for suppressing the rally", he said.
The group has linked to videos of protesters asking the school's administration to stop the speech.
Darnell said Scott's executive order was not meant to "alarm anyone", but to make sure that her office has the "resources and equipment to help us prepare for violence or widespread property damage".
But state's flagship university had to let Spencer speak on campus eventually.
"We are hoping this is a nonevent", Darnell said. The event is unaffiliated with the school, and no student groups sponsored the speech or invited him, the university said. "But we don't know that, so we're taking it very seriously", Darnell said.