Can an ordinary citizen influence politics?

An ordinary citizen is able to influence politics, but in reality such influence is reduced to zero. But still, it is worth highlighting the ways of influence, namely, participation in elections, that is, a citizen supports his candidate by transferring his vote, and in case of victory, endowing the candidate with a carrier of his interests; the opportunity to participate in mass promotions. Also, an ordinary citizen can try to be elected independently, but at the same time he will have to go through many elections (from the district and city, to the federal level).