probably not.
human ski, when dry, has resistance in the range of 100 kilo ohms, while steel has a resistivity of 0.1 millionth of a ohm. the resistivity of human skin, when dry is almost 10 order of magnitude greater than steel and the current will prefer a path through steel rather than human, even if you touch that particular steel. Its only if the wire directly falls on you that you'll be in extremely high danger as in that case your body will form a series connection with the metallic body of train and thus current will have to flow through you.