He brought a bit of fire to “New Lab.” (5)
I believe the answer is:
blair
'he brought a bit' is the definition.
The definition suggests a singular noun which matches the answer.
'fire to new lab' is the wordplay.
'fire' becomes 'ir' (I can't justify this - if you can you should believe this answer much more).
'to' says to put letters next to each other (I've seen this in other clues).
'new' indicates an anagram.
'lab' is an anagram of 'bla'.
'ir' put after 'bla' is 'BLAIR'.
'of' is the link.
Can you help me to learn more?
(Other definitions for blair that I've seen before include "Major's successor as PM" , "Former prime minister" , "former leader" , "Tony . . . . ., British ex-PM" , "Labour leader from 1994" .)