Absolutely, Randy. Thoughts create electrical impulses in the brain. The sheer presence of electricity creates a magnetic field (the Ampere-Maxwell equation of electromagnetics in physics). And magnetic fields attract. So change the thoughts in order to change what one is attracting.
As far as destructive thoughts are concerned, I remember this saying: "You don't have to believe everything you think." I don't know where I heard that first, yet it helps me release those destructive thoughts. (Does anyone know the author to which I should attribute the saying?)
Also, thought patterns are "contagious"- they can be passed from person to person, especially when people are in close physical proximity. "Highly sensitive" people are more conscious of this transfer.
I do my best to spend time with people who have loving and wealth-affirming thought patterns, to let these factors work in favor of strengthening my prosperity consciousness.