"有成功或胜利把握" can be translated into English as "have a good chance/ assurance of success or victory" or "be confident of achieving success or victory".
Here are some example sentences to illustrate the usage:
We have a good chance of success if we work hard. （如果我们努力工作，就有成功的把握。）
He is confident of achieving victory in the upcoming competition. （他对即将到来的比赛取得胜利充满信心。）