The phrase "advocata nostra" in English "gracious advocate" is a profound role attributed to Mary.
Mary can act on this particular role powerfully "Advocate for the People of God" by virtue of the heavenly reward bestowed on Her by the Most Holy Trinity at the end of Her earthly life.
The Blessed Virgin Mary: Advocate for the People of God
I found the back cover translator's notes of the small book compiled by a deceased Bosconian Priest Fr.Adolf Faroni, SDB fascinating. The title of the book taken from St.Bonaventure words "Mary, the jewel of the human race", it composes of words of praises and quotes coming from 99 famous Saints & Church Fathers and Popes.Also, it contains a beautiful prayer to Mary coming from St.John Paul II the Great whose known for the famous line "Totus Tuus" composed during the Celebration of the Marian Year.
Below is the back cover tranlator's notes describing the "Salve Regina"
"Then the Eternal Father announced to all the angels & saints; "Our Daughter Mary has been chosen by our will from among all creatures as the first in our favor, and she has never fallen from the position of a true Daughter.Therefore, She has a claimed to our Kingdom, of which She is to be acknowledged and crowned the lawful Sovereign and Queen".
The Incarnate Word declared; "To my true and natural Mother belong all the creatures that I have created and redeemed.And of all things over which I am King, She too shall be the rightful Queen."
And the Holy Ghost said; "By the title of my only chosen Spouse, to which She has faithfully corresponded, the crown of Queen is also due to Her for all eternity."
Then the three Divine Persons solemnly placed on Mary's bowed head a splendid gleaming crown of glory which far exceeds in beauty any crown that ever has been or ever will be rewarded to a creature by God.
At the same time a Voice sounded from the Throne saying; "Our Beloved and Chosen One among creatures, Our Kingdom is yours.You are the Queen and Sovereign of the Seraphim and of all our ministering angels and of all the created universe.We give you power,majesty and dominion over it. While filled with grace beyond all others, you humbled yourself to the lowest place in your own estimation. Receive now the Supreme Honor which you deserve, and participate in the Sovereign Power exercised by the Divinity over all that Our Omnipotence has created. From your Royal Throne you shall rule over hell and earth and nature. Our own Will shall ever be ready to accomplish your will.
Book : "Mary the Jewel of human race" (complied by Fr.Adolf Faroni, SDB)
Daniel V. Flynn, J.C.C
Patrick J. Sheridan, D.D.
vicar General, Archdiocese of New York
From Fr.Adolf Faroni,SDB back cover narration of Salve Regina, it shows that the most Holy Trinity had crowned the "Blessed Virgin Mary their Beloved Daugther, Theotokos and Spouse" and bestowed Great Power to Her by crowning Her Sovereign Queen of Heaven & Earth. as seen in sacred scriptures in Revelation12:1 a Catholic Church belief that is pointing to the Blessed virgin Mary as also the Woman in Genesis3:15. And so the title of Salve Regina empowers the Blessed Virgin Mary to act as a powerful Advocate in the words of the famous Latin hymn "Advocata Nostra".