One likely to lose is urged on anyhow, maintaining decorum initially (8)
I believe the answer is:
underdog
'one likely to lose' is the definition.
'urged on anyhow maintaining decorum initially' is the wordplay.
'anyhow' indicates an anagram.
'maintaining' indicates putting letters inside.
'initially' suggests taking the first letters.
The initial letter of 'decorum' is 'd'.
'urged'+'on'='urgedon'
'urgedon' with letters rearranged gives 'underog'.
'underog' going around 'd' is 'UNDERDOG'.
'is' is the link.
(Other definitions for underdog that I've seen before include "One thought to have little chance of winning" , "No drudge (anag.)" , "Weaker contestant" , "One of low status" , "Likely loser" .)