It can be challenging to find synonyms for the term "strong partisan," as this phrase essentially means someone who is deeply committed to a particular political ideology or party. However, some possible alternatives might include terms like "ardent supporter," "die-hard loyalist," "unwavering advocate," or "zealous adherent." Other options could include more specific descriptions, such as "conservative stalwart" or "liberal firebrand," depending on the individual's political leanings. Ultimately, the key factor that characterizes someone as a strong partisan is their unwavering dedication to their political beliefs, regardless of the specific terminology used to describe them.