What voter can contribute to the Far Right? (6)

I believe the answer is:

across

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'to the far right?' is the definition.
(across to one side)

I don't understand the remainder of the clue.

(Other definitions for across that I've seen before include "Traversing" , "First word in any crossword" , "14 of these clues are" , "As this is entered" , "stride - athwart" .)

I've seen this clue in The Times.

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