"积极参加竞选"可以翻译为 "actively participate in the election campaign" 或 "take an active part in running for an election"。
actively participate in the election campaign：
"actively" 表示“积极地”；
"participate in" 表示“参与”；
"the election campaign" 表示“竞选活动”。
take an active part in running for an election：
"take an active part in" 也表示“积极参与”；
"running for an election" 表示“参加竞选”。