Preferential boosting

[Lance Norskog]

Suppose I have a schema with an integer field called 'duration'. I want to
find all records, but if the duration is 3 I want those records to be
boosted.
 
The index has 10 records, with duration between 2 and 4.  What is the query
that will find all of the records and place the records with duration 3
above the others?
 
These do not work (at least for me):
 
    *:* OR duration:3^2.0
    duration:[* TO *] duration:3^2.0
    duration:3^2.0 OR -duration:3
 
Thanks,
 
Lance Norskog