What is this critter?

One of the ladies on the HSS Yahoo group, asked us to identify this rodent.  She lives in Northern Colorado.   From the end of its tail to its nose the creature is an easy 12 inches in length.  The tail itself is about 6-8 inches and is furry but not bushy.   The body is  white underneath  and it has long black whiskers.   It has been suggested that it's a roof rat of some sort.....what do you think?

It's been living in the hood of her van and they've been trying to capture for about 2 weeks now.  Nothing has worked.  Any ideas on how to capture it?








ETA:

Hey, I think it's a PACK RAT!!!  No kidding!  It's really known as a bushy-tailed woodrat, but it where we got the term "pack rat" from. 

Check these pictures out:


Northern Prairie Wildlife Research Center

Wiki

National Parks


11/5 ETA:

Or maybe it's an Eastern Woodrat
Look here


Or perhaps it's a White-throated Woodrat?
Click here to see one


Lisa adds this information:

I think they might have hitched a ride from KANSAS (where our home was made)  I really really  hope not; but it is kind of making sense.  We have our share of field mice; but the scurrying in the walls and roof is more than usual! Something was getting either in the walls or between the outside of the house and vinyl siding!  Talk about creeps! 

 

I never thought of making sure of nests in the ceiling before they put the home on the foundation!  The ceiling is not blown the fiberglass ; but rather fluffy loose blown in insulation...making more of a chance they would nest.