"Mugwumps" is a word that is rarely used in modern English. It originally referred to a group of Republican politicians who remained neutral in the 1884 presidential election, a term that has since taken on a negative connotation to describe someone who is undecided or unwilling to take a stance on an issue.
There are several synonyms for mugwumps, including fence-sitters, neutrals, waverers, and undecideds. Other terms that can be used include equivocators, ditherers, and vacillators. These words all share the common meaning of someone who is uncertain or hesitant. Alternatively, terms such as independents, nonpartisans, and centrists can be used to describe individuals who maintain a neutral stance when it comes to politics.