There is no doubt that the Holy Qur'an has acknowledged intercession and tawassul between Allah and His people, and not prohibited that nor prevented His messenger from it. Rather, the Qur'an has made it permissible and recommended it.
The Qur'an has made the Prophet’s doings, sayings, and approving of others’ doings as example for us to follow in our lives, when saying:
Certainly you have in the Messenger of Allah an excellent exemplar.[1]
On this basis, we will take the Prophet’s doings and sayings as our evidences. We shall not derive our evidences from the books of the Shia nor all the books of the Sunni, for that shall be uncountable. We shall be satisfied with what al-Bukhari has mentioned in his Sahih alone, so that the answer to the Wahabis shall be by the knockout that they may not argue after it if they are fair. Otherwise, their obstinacy and blind fanaticism shall expose them before all Muslims.
After we have proved the permissibility of tawassul from the Qur'an and the Prophetic Sunna, we discuss what is, to the Wahabis, more defamed and more deniable than tawassul is; it is the asking blessing of and wiping one’s body (against holy shrines and sacred places).
The Wahabis have reached an extent that they beat the hajjis for doing so and accuse them of polytheism.
source : http://www.maaref-foundation.com