Include as an author someone who contributed to financial support only?
I think (hope) that most people in academia would consider it improper to include, as an "author", anyone who didn't contribute to the content of the paper. There are some exceptional cases that are questionable, but this one seems pretty clear. 

But the paper might properly include an acknowledgement section naming the person and thanking them for their help in obtaining funding for the project.

But I recommend not degrading the meaning of authorship by naming others. 



Note that some of the exceptions, such as including a PI as an author, are justified, at least in part, because the PI, in addition to funding and running a lab/project also contributes general guidance and conceptual background to the work that goes on there. They have a continuous presence that impacts all the work in the lab. And some consider this to be improper, also. But it is highly variable by field.