Kind of a poor photo... I found seed of this Penstemon just outside Canyonlands on a roadcut. Serrated green-grey leaves with stalks that were about 24" - 30" tall.
Looks like a member of Section Coerulei, but none of those has serrated leaves. The leaves look entire to me.
Penstemon angustifolius var. vernalensis.
extreme western edge of Denver, Colorado; elevation 1705.6 meters, average annual precipitation 30cm; refuses to look at thermometer if it threatens to go below -17C