[Word] Find and Replace

[Gene St. John]

I have a need to replace many instances of _______1.^t, none of which 
were entered with a style and some of which have shorter underscores 
than others and all of which have different numbers. The replacement is 
a style called multiple choice and it has a shorter underscore than the 
original and a capability to iterate the number. I have used 
_______[0-9]{1,2}.^t to find the original (no numbers above 19) and 
Format:Multiple Choice in the Replace text box.
The execution of the Find/Replace works well except: It won't find 
varying lengths of underscore and the original is not replaced.
I can run the Find/Replace a second time with the Format removed and the 
original is replaced, leaving the replacement style. Works, but a bit 
hokey. I would certainly appreciate some fine tuning. Thanks.
Gene