Common chicory (Cichorium intybus, Asteraceae) exists throughout North America. You can consider it a weed or a wildflower, depending on your perspective. I think it’s rather attractive, but it tends to pop up in my yard where I’d prefer not to see it. In late July it’s ubiquitous along roadways in southeast Michigan.
The bright blue “flower petals” are actually a nice example of bracts: modified leaves that attract pollinators to the flower. The flower itself is quite small, located in the center of the bracts.