National Transportation Safety Board officials have issued a preliminary determination pilot error contributed to the accident, and the senator was flying a single engine aircraft in IFR [instrument flight rules] conditions while only having obtained a VFR (visual flight rules) rating.
The absence of a post-crash fire was likely due to insufficient fuel on board. No one on the ground was injured.
Photograph below was taken at the scene to show the extent of damage to Senator Clinton's aircraft.
She was very lucky.