MAGA line might hit around Republican hotspots (7,7)

I believe the answer is:

thermal imaging

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'hotspots' is the definition.
I can't tell whether this defines the answer.

'maga line might hit around republican' is the wordplay.
'hit' is an anagram indicator.
'around' means one lot of letters goes inside another.
'republican' becomes 'R' (abbreviation).
'maga'+'line'+'might'='magalinemight'
'magalinemight' anagrammed gives 'themalimaging'.
'themalimaging' enclosing 'r' is 'THERMAL IMAGING'.

Can you help me to learn more?

(Another definition for thermal imaging that I've seen is " detection technique".)

I've seen this clue in The Independent.

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