DK: The question is the conditional effect of income on how either dem or non-dem affects feeling toward Obama. From two linear models, it seems the conditional effects (interation terms) are statistically significant! Note that the effect of income on Obma for non-dem becomes = 0.014329 + -0.067813*nondem. since nondem = 1, it become -0.053484. On Whether the point estimates are statistically significant, it needs further analysis. But, we can at least answer the question right?