Is the US Presidential race rigged?

Yesterday, in class, we discussed the current primary race. The link below is an article from BBC that discusses the delegate system and the issues that have come up as a result of the "fuzzy" delegate math. Do you think the United States election process is rigged? Do you think that there could be a better method of holding elections?

http://www.bbc.com/news/election-us-2016-36029381