Article 175
The freedom of expression and dissemination of thoughts in the Radio and Television of the Islamic Republic of Iran must be guaranteed in keeping with the Islamic’ criteria and the best interests of the country. The appointment and dismissal of the head of the Radio and Television of the Islamic Republic of Iran rests with the Leader. A council consisting of two representatives each of the President, the head of the judiciary branch and the Islamic Consultative Assembly shall supervise the functioning of this organization.

Everything seems sound up to the point that every programm is limited to “Islamic criteria and ineterest of country”, which can be loosley interpreted.
Another matter which limits free public access to information is made by the following article:

Article 44
The economy of the Islamic Republic of Iran is to consist of three sectors: state, cooperative, and private, and is to be based on systematic and sound planning. The state sector is to include all large-scale and mother industries, foreign trade, major minerals, banking, insurance, power generation, dams and large-scale irrigation networks, radio and television, post, telegraph and telephone services, aviation, shipping, roads, railroads and the like; all these will be publicly owned and administered by the State. …

According to this one, having private channels is ruled out by the government and naturally everything else, broadcasted over TV or Radio is controlled by the state. There has been different attemps (mainly by Karroubi, a current presidency candidate) to establish a private sattelite TV station called Saba, which lead to failure.
Realated to current elections, different programs was organized by main TV station i.e. each candidate was given 30 minutes for a “documantary film” evolving around their future plans and perspectives, and also pairwise debates between candidates.
Newspapers are mostly controlled by conservatives and even hardliners,the only one published by reformists is called “Etemad Melli” which license also belongs to Karroubi.
So it’s obvious that generally “state media” cannot be considered as covering or even reliable sources of information. Exactly because of this fact, candidates (mostly reformists, whose campaign get no sound coverage) try to contact their audiences face to face, may it be by meetings in universities or by visiting different provinces.
Another popular way (particularly by current election) is to make use of independet online media, a great option as about half of Iran’s population is under 25 years old.

I hope that I’ve answered your question.