President Barack Obama will designate 4,726 acres in southwestern Colorado important to environmentalists and Native Americans as a national monument on Friday under the Antiquities Act.

According to the Denver Post, Chimney Rock, a site native Americans find to be a spiritual site, will be managed by the United States Department of Agriculture and the Forest Service. Ranchers will maintain grazing rights in the area. 

This is only the third time Obama has used the Antiquities Act to designate an area as a national monument, and this action comes during a week in which Colorado, which Obama won by nine points in 2008, moved toward Republican challenger Mitt Romney in the polls. 

Obama only leads by 1.3 percentage points in the average of Colorado polls. In the three most recent polls, Obama led by a statistically insignificant one percentage point in two polls, while Romney led by two points in another. 

Colorado was once thought to be a shoo-in for Obama in 2012, but the state has become a true tossup state that may in fact be leaning toward Romney.