JOEL - The word "saint" is not used in the same way as for example the Catholic Church uses it. Everyone who is a member of the Mormon Church is considered a saint.
First of all the official name of the Church was received by revelation through the Prophet Joseph Smith. It is what God wanted His church to be called in these latter-days (See Doctrine and Covenants Section 115).
Secondly, The Church of Jesus Christ of Latter-day Saints sees itself as a restoration of the original Church of Jesus Christ "of Former-day Saints." Members of the Church in the time of Christ were often referred to as "saints."(Rom 1:7, Eph 2:19, Col 1:2,) Actually, the word "saint" predates Christ, and it is used thirty-six times in the Old Testament. It appears sixty-two times in the New Testament. The term "Christian" appears only three times in the New Testament, used by others to identify the followers of Christ. At the time of Christ and the Apostles, the term "saint" was accepted as a proper name for anyone who was a member of the Church, and was not used as a term of special sanctity as in earlier and later traditions. By referring to themselves as Latter-day Saints, members of the Mormon Church reaffirm their historical tie to original Christians (the Former-day Saints of the New Testament) but differentiate the two time periods.
Also, they are striving to become sanctified through obedience to the laws and ordinances of the gospel.