Manifort was hired to navigate the Republican nomination process. When Manifort's personal business dealings with a Russian supported very corrupt Ukranian regime became known and the presidential campaign was down 17% in the national polls, he was asked to resign. It will be interesting to see what Mueller has on Manifort and Kelly. I suspect it will be for failure to register as an agent of a foreign power and money laundering. Once the charges are filed and he has something to show for the tens of millions spent I expect that Mueller will conclude his special investigation.