Chauliognathus pennsylvanicus - Goldenrod Soldier Beetle. Images can be found in the guide here. We were a little surprised since this is usually a late summer creature but then realized you hadn't listed a date, so you may very well have taken this in late summer. The species out at present, the Margined Soldier Beetle, has a black mark on the pronotum (the plate covering the front of the thorax) that runs all the way from the front to the back.
(As you get more interested and post more images (and we hope you do!) it will help if you fill in more of the fields on the image subbmission form. The more information the experts have, the more likely they can give you a solid ID.)