Translation

勢力を増している / 優勢な / 上昇中の

Meaning

Ascendant describes a person, group, idea, or influence that is rising in power or becoming dominant. It is formal and often appears in politics, culture, business, and analysis.

Examples

• その政党は若い有権者の間で勢いを増しています。
  The party is ascendant among young voters.
• デジタル決済はその市場で優勢になりつつあります。
  Digital payments are ascendant in that market.