Take Occupy Wall Street for example. There are a number of homeless occupiers. The well to do anarchists in occupy, living home with their parents, care nothing for them. They would gladly sacrifice the homeless amongst them if they thought it would advance their anti establishment ideals. And so therefore when occupy had a large amount of money in its general fund, there was no real attempt to help the long term homeless not become homeless. Ridiculous solutions such as short term housing in the churches were put in place.
Look at the nation as a whole. One way poor blacks and hispanics were successfully marginalized was to separate them from society. Give them help in the form of public assistance, put them in housing projects, and psychologically isolate them from the rest of society. Make them self aware that they are poor victims, and then the poor victims will become too psychologically crippled to function outside of ethnic enclaves. This is marginalization. As Wikipedia explains:
"In sociology, marginalisation (British/International), or marginalization (U.S.), is the social process of becoming or being relegated to the fringe of society e.g.; "the marginalization of the underclass", "marginalisation of intellect", etc."
In short, marginalized groups exist at the fringe of society, or they are not even considered to be a part of the society. The leftists organizations and groups exploit marginalized people by telling them they can never be a part of the mainstream, and by giving them certain types of aide to keep them dependent on the left. This can be welfare, or on a smaller level, this can be the church housing,metrocard, and food programs in occupy wall street.
An interesting thing about marginalized groups is a neighborhood full of the marginalized, say poor blacks, is said to be a bad neighborhood. For years places like Harlem, Bedford Stuyvesant, among others, were considered horrible places. But the fact is that they were always very close to business centers in Midtown and Downtown Manhattan, to airports in the NYC region, and to everything else the city has to offer. Whites and Asians began moving into these neighborhoods in large numbers because it was close to their sources of income, and these neighborhoods ceased being bad neighborhoods. So the problem wasn't that the area was actually bad, the problem was the people in the area were cut off from societal participation.
How can marginalized groups break out of being marginalized? One if for people to realize we all have the rights to be where we want to be. Marginalized groups often have extremely low self worth and esteem, and this mentality makes them afraid to operate outside of the so called "community". On an individual level people have to boost their self worth, realize that we're all human, and go for all they want or need. Increased contacts with people who are not living in abject poverty would increase the chances of employment, or of learning the system well enough to be gainfully employed.
Successful non whites in this country, such as the Obamas, Colin Powell, Condoleeza Rice, Richard Parsons (former Time Warner CEO), Kenneth Chenault (American Express CEO) all had successful careers precisely because they were not marginalized. The East Asian and Indian students and professionals across college campuses, in medicine, in engineering, etc also aren't marginalized, and therefore they do well in their careers. In short, find ways to bring the marginalized out of the holes they were condemned to, not only do you end their poverty, but you end the jobs of many leftists.