The most common and most likely answer to this crossword clue is the 10 letter word FEDERALIST
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More clues leading to the result FEDERALIST
- Politician and tennis player, without hesitation the top celebrities
- E.g. Yankee leader messily tucked into pud
- Constitution’s supporter supplied ruler with an agenda, for example
- Union supporter surprisingly is left outside backing a communist
- Heartless first leader disturbed one backing union of states
- Type of politician feared, awful heel
- Differentials Al solved before final removal by one supporting a stronger centre
Buddy explains!

The straight part
We know that "E.g. Yankee" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case e.g. yankee = federalist.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 FEDERALIST mean?
FEDERALIST noun- Advocate of federalism.
- Supporter of the view that the province of Québec should remain within the Canadian federal system; an opponent of Québec‐based separatism or sovereigns.
- A covenantalist.
- Of or relating to federalism, or its advocates.