The Washington Post has a nice Democratic nomination simulator which allows you to make various assumptions about the candidates. “You should also notice that, in most scenarios, it takes a while for a candidate to get a delegate majority and, therefore, the nomination. In some scenarios, no one may, meaning that the party gets to its convention without a clear nominee — the dreaded ‘contested convention’ scenario.” “What may be more subtle is how hard it is to overtake a front-runner.