Geokit - find within fuzzy locations

I'm using Geokit gem to query mappable records within some distance to a
mappable user.

When geocoding an address such as "Madrid", lat&lng represent a point,
in this case the center of the city.

Suppose I have some records with location "Madrid", which are mapped
with lat & lng to the center of the city. When querying for the closest
record, the inaccuracy of the address will prevent the query from
working appropriately. If the user's close to the center, records that
are anywhere in the city might be returned anyway.

A similar effect would happen if the user's location is inaccurate.

Is it possible to take into account the "size" or "fuzziness" of the
location in geokit queries?