The song Chola maati ke raam is actually a bhajan, written by Gangaram Sakhet. The lines chola maati ke raam, ekar ka bharosa chola maati ke re, according to me mean that there is this statue of Lord Raam made of earth, and he's the only one who we can believe, we can rely on (in this time full of problems).
Actually in the meaning here I have not found the meaning of chola which according to me means a gown or a robe which sadhus wear. Wonder what it means here, but the lines probably have more or less the same meaning I guess.
Any suggestions with a better detail are welcome.
Update: it means that the poet is preaching that the body is a robe made out of clay (mitti) and one should dedicate their lives to Ram since he is the only hope. (Courtesy: Rohity, see comments below)