Use the 7.x-3.x version of Google Analytics Reports
As of Jul 31, 2015, the Google Analytics Reports module completed the Migrating from the Chart to the Charts module. Refer to my answer to "How to transform data from the Google Analytics Reports module into charts?" for new options (features) that became available as of the 7.x-3.x version of that module, and which may better fit your needs.
Roll your own cookies
If you'd rather want to consider an alternative, you could try to create those charts, by just using the Charts module to achieve your goal. After importing relevant data (as suggested in another answer also), you could use either its Views integration, or its API (in your custom module). The Charts Community documentation may help to do so also.
Specific to your question here, there is an interesting Charts-issue you may want to look at. I.e. Graph node input over time (support date formatting on a continuous axis). In Comment #3 of that issue is stated: 'The trouble here is that neither Views nor Date modules provide aggregation options for date-based fields.'.
Part of the recommended solution there is to (also) use the Views Date Format SQL module. Here are some details (from its project page):
The Views Date Format SQL module allows to format date fields using SQL. This enables group aggregation for date fields using the choosen granularity.
The core functionality is to remove the date formatting from render() and put it in query(). I.e. format date values using SQL's DATE_FORMAT rather than PHP's format_date. This is achieved by assigning a new default handler to node 'created' and 'changed' date fields. This handler extends and overrides views's build in views_handler_field_date.
The UI is completely unobtrusive, only a single checkbox "Use SQL to format dates" is added to the handler configuration popup.
Disclosure: I'm a co-maintainer of the Charts module.