Yes, Hillary Clinton very likely had meetings with lots of political contributors. As a milestone for the Democratic party, many political contributors will want to chat with her just as she will with them. The lack of several entries in the state department could either be for reasons of secrecy of just simply because there were too many meetings to keep up with.
Hillary Clinton, like all majority of US politicians, will gladly accept contributions. But I must say that it seems rather odd that her calendar is missing several dates. Perhaps she was meeting with someone whose reputation would bring about negative points to her campaign? This only proves that all politicians, especially those that are powerful as Hillary, should be transparent in all of their actions.
There is substantial evidence that while Hillary Clinton served as secretary of state that she had numerous meetings with top political contributors. In fact, some of Clinton's recovered emails reference meetings with business leaders, and donors of the Clinton Global Initiative. In short, there is a strong likelihood that Hillary top political contributors were able to buy access to Clinton while serving as secretary of state.
Hillary definitely engaged a lot of political contributors and that explains her calendar missing several entries. This is not a bad thing at all because a person looking to be the next president of united states, she must be close with political contributors. This was nothing but a strategy to consolidate her standing in the race.