Twee‧dle‧dum and Twee‧dle‧dee /twiːdlˌdʌm ənd twiːdlˈdiː/
two people or groups who are almost exactly the same as each other, especially when they both seem to be bad. The names come from two characters in the book Through The Looking-Glass by Lewis Carroll. They are fat little men, who are both dressed in school uniform and look exactly like each other:
Some voters felt there was little real difference between the two party leaders – a case of choosing between Tweedledum and Tweedledee.

[TahlilGaran] Dictionary of Contemporary English ▲