Possible Clues:

• Latino on tour, in theory only
• Somebody else supported by a line? Only in theory
• Imaginary - in on a lot (anag)
• Imaginary number transformed into a real finally
• Other than a lion — perhaps something less concrete
• Citizen has love for one American capital? That's hypothetical
• "She's been a little ––, she's had her head addled by women's talk" (William Dean Howells, Dr Breen's Practice)
• Anything but Scottish island with lake is imaginary
• Hypothetical, assumed to be correct
• La Gioconda