Nationally, Democrats raise significantly more money than Republicans[0], especially from small donors[1]. It wouldn't be surprising to me if this skew was stronger for people working in government.
It's not as odd when you look at employment length. One of the stats I've seen is that Democrats who go into the civil service are more likely to stay long term. Republicans are more likely to leave for the private sector.
I'd expect employees who have been there longer, and so are likely making more money, to be both more likely than shorter term employees to make political donations and to be likely to make bigger donations than those shorter term ones that do donate.
