Political bosses and machines manipulated immigrants for their votes in order to help them rise above social prejudice and unemployment in the late 1800s.
For example if an immigrant was struggling to find work, a political boss may offer them a job working in a factory. In return, the immigrant would be expected to vote for the political candidate that the political boss told them to vote for. This system of bribing resulted in huge corruption and fraud, especially in big cities like New York and Chicago.