The most common and most likely answer to this crossword clue is the 8 letter word RECOVERS
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More clues leading to the result RECOVERS
Buddy explains!

The straight part
We know that "Rallies" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case rallies = recovers.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does RECOVERS mean?
RECOVERS verb- To get back, to regain (a physical thing; in astronomy and navigation, sight of a thing or a signal).
- To salvage, to extricate, to rescue (a thing or person)
- To replenish to, resume (a good state of mind or body).
- To obtain a positive judgement; to win in a lawsuit.
- To gain as compensation or reparation, usually by formal legal process
- To reach (a place), arrive at.
- To restore to good health, consciousness, life etc.
- To make good by reparation; to make up for; to retrieve; to repair the loss or injury of.
- To get better, to regain health or prosperity
- To regain one's composure, balance etc.
- To cover again.
- (roofing) To add a new roof membrane or steep-slope covering over an existing one.