Senator Klobuchar (D. Minn.) appears to have made enemies.
The attacks appear to be the kind of attacks often made against powerful women.
On the other hand, not being able to treat at least some of the people who work for you well is often a bad sign. George Marshall, for example, was famously hard on senior officers who worked for him, having both very high standards and being famously reserved and impersonal. However, Marshall was also know for the courtesy and professionalism he demonstrated in dealing with NCOs and enlisted Soldiers.