That is our most common and quite harmless white-lined sphinx, Hyles lineata. Their early summer larvae are also among our prettiest hornworms, too. late summer lends mostly black and yellow longitudinally-striped larvae, but all the moths will still look like these.
Nancy, if you wish to attract more lineatas, I highly recommend Mirabilis [4 o' clocks]. The late afternoon/evening blooming flowers draw in the moths, which pollinate them. Any long, slender, trumpet-shaped flowers can only be effectively pollinated by hawkmoths and hummingbirds. Mirabilis is also food for the lineata larvae, so just be aware that any large hornworms you find, need to remain on the plant, and will not actually harm it. Sphinx moths know how many eggs to lay on a plant. Mirabilis is also a perennial in most states, too.
I've had them for 2 years previous to the last. Maybe it was too hot & dry. It was flitting about the agastaches & greggii salvias. Only noticed them at dusk. Could hardly see the first time I saw one.