Dance — pick second half or pick again (7)
I believe the answer is:
reelect
'pick again' is the definition.
(I've seen this before)
'dance pick second half' is the wordplay.
'dance' becomes 'reel' (reel is a kind of dance).
'pick second half' becomes 'ect' (I can't justify this - if you can you should give a lot more credence to this answer).
'reel'+'ect'='REELECT'
'or' is the link.
Can you help me to learn more?
(Other definitions for reelect that I've seen before include "Bring to power again" , "put back in" , "Return to seat" , "Put in power again" , "Vote into office again" .)