Which form of Buddhism stresses salvation by faith in Amida?

Answer 1

I think you are talking about Jodo Shinshu a school of Pure Land Buddhism. Wikipedia under the Shinran(the founder of Jodo Shinshu) topic says

"Pure Land School of Buddhism encouraged its practitioners to rely on the vow of the Buddha Amitabha (Sanskrit, Amida in Japanese) to save all beings from suffering. According to three particular sutras Amitabha vowed to ensure that anyone who chanted his name would be reborn in his Pure Land of Sukhavati (Sanskrit, lit. Land of Bliss) and once there would easily be able to gain enlightenmnent, because they would not be hindered by the problems of day to day life... He taught that awakening to the saving grace of Amida Buddha is the central matter. Continuous chanting of the nembutsu (namu amida butsu) , is not necessary, as Hōnen, his mentor, had believed. Instead, Shinran taught his followers that the nembutsu should be said as a form of gratitude rather than a way of achieving rebirth in the Pure Land. Faith in Amida Buddha would lead to a deep spiritual awakening, called shinjin, which severs the practitioner forever from birth and death in the world of samsara, and erases karma accumulated through many rebirths. Shinran taught that the advantage of the Path of the Nembutsu can be experienced here and now. The arising of shinjin also assures the devotee of birth in the Pure Land, and the attainment of enlightenment there."