90% of people support him, but a handful of people have slandered him.
90% of people are on his side, but a small number of people have made disparaging remarks about him.
ー90% of people support him, but a handful of people have slandered him.
「9割の人々は彼を応援するが、一握りの人々は彼を中傷した」
to support で「応援する・支持する」
a handful of people で「一握りの人々」
to slander で「中傷する」
ー90% of people are on his side, but a small number of people have made disparaging remarks about him.
「9割の人々は彼の味方だが、少数の人々は彼を中傷した」
to be on one's side で「人のサイドにつく・味方する」
a small number of people で「少数の・わずかな人々」
to make disparaging remarks で「中傷的な発言をする」
ご参考まで!