Diocese of Portland Prayer For Vocations:
The prayer specifically written for our diocese by Bishop Joseph Gerry:
Loving Father, you sent your Son so that all might come to know the truth and be saved. With the outpouring of the Holy Spirit, you continue his work through the Church. Your Son reminded his disciples that the harvest was indeed plentiful but the laborers few. Following his instructions, we beg you to call many to ordained ministry and religious life. Grant them the grace to hear you and to respond wholeheartedly. May Mary Immaculate the mother of your Son, and the patroness of our diocese, intercede for us. We ask this through Christ our Lord.
For a very extensive collection of vocations prayers, the USCCB collection is very helpful: