@Quetzal:
There is plenty of research showing that intergenerational wage mobility is greatest with conservative men than more liberal leaning counterparts. This sociology research goes all the way back to the 60s. It also points out that extremism of any sort (whether it's religious or political) is associated with downward mobility.
That doesn't mean everyone who votes Republican will suddenly have their kids become rich, but it's statistically a better chance that within 1 or 2 generations you are lifted out of poverty.
The simple fact is that conservative values (dual parent households, get married and have a job before kids, take care of your parents and grandparents, don't be a criminal) are associated with much greater wealth generation indicators, it generates more income in a household and less instability if one income drops off and thus less reliance on crime to supplement income.
This has nothing to do with your race by the way, sure, any minority group will have it more difficult because they are a minority group and thus need to do more to get out of whatever well they are in, but likewise, minority groups that are lawful (eg. immigrants and racial groups alike) will almost certainly have their kids do better vs minority groups that are illegally residing here and kids with parents that are criminals.
As far as why Democrats suddenly started making inroads in the black community is pretty easy to find out: the kids growing up post-civil rights became reliant on government cheese. Democrats started giving out more and more handouts in an effort to destabilize black economies. Eventually all the racists died off but the policies remained. The policies Dems like FDR designed in the 40's and NYC and other cities and states as well were specifically coded to destroy Black communities, for example, NYC had a policy that if you took welfare checks and a black male was present in the residence during a random welfare check (which were targetted), welfare checks were discontinued - as a result you have less black males, both fathers and other role models in the house. Just like Planned Parenthood's original motivation was to reduce black babies being born, the motivation of welfare was to disrupt and reduce the black population.
So yes, institutional racism existed until the late 60s and as a result, welfare policies were designed with a racist background. However the welfare never went away, the Dems simply rebranded them as 'good' and 'helping' and a generation of black people forgot the reason they were designed the way they are and is now wholly dependent on it. Breaking a dependence on free stuff is hard, even though FDR explicitly said that his policies were not intended to last, we have them, almost a hundred years later, in their original form and any politician that says he wants to get rid of Social Security and Welfare is committing political suicide.