Start with handle for conspiracy theorist? (5)

I believe the answer is:

crank

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'start' is the definition.
(I know that crank is a kind of start)

I can't explain the remainder of the clue.

(Other definitions for crank that I've seen before include "Person with strange ideas, or machine part" , "Turn (engine handle); eccentric" , "Person of eccentric habits" , "Eccentric - starting handle" , "Person with strange and often aggressive ideas" .)

I've seen this clue in The Sun.

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