Dry Hands for Netilas Yadayim

Question: Do I need to ensure that my hands are totally dry before washing them before eating bread?
Answer: The Gemara (Shabbos 14b; Eruvin 21b) teaches that Shlomo Hamelech instituted the mitzva of washing one’s hands before eating teruma, as one’s hands may have come into contact with items that are tamei, ritually impure. According to the Gemara (Chullin 106a), this law was extended to everyone washing before eating bread, so as to ensure that kohanim would become accustomed to wash their hands before eating.
There is a machlokes, however, as to whether one needs to ensure that one’s hands and the cup handles are dry before washing.
The Rema (OC 160:11) quotes the Terumas Hadeshen (259) who holds that a basin of water which has been touched is suitable for use for washing one’s hands. Only water that one used to wash one’s hands with, becomes tamei and unfit for use again.
Following this, the Chazon Ish (OC 24:20) writes that if one’s hands were wet before washing, the water on one’s hands becomes tamei, and does not become tahor by being washed. As this invalidates the washing, both one’s hands and cup handles need to be dry before washing.
However, the Magen Avraham (162:10), Mishna Berura (162:27; Biur Halacha 162:2; Shaar Hatziyun 162:41) and R’ Benzion Abba Shaul (Ohr Letzion 2:11:9) write that one does not need to ensure that ones hands are dry before washing. The Mishna Berura quotes the Pischei Teshuva who writes that one should ensure that the cup handles are dry before one touches them. Nonetheless, he disagrees, writing that this water does not become tamei, and therefore it does not invalidate the washing (See Eretz Zvi 35).
In conclusion, one may wash one’s hands even if they are wet, though many are particular to ensure that they are dry first.