Ex-President Khatami, seen as a model for reformists
Iranians go to the polls on 14 March to elect representatives for the country's parliament - the Majlis.
More than 4600 candidates representing 30 provinces will be vying for 290 seats in the Majlis. Five seats are reserved for religious minorities.
What are the restrictions on candidates?
Majlis candidates must be Iranian nationals aged between 30 and 75 years of age with a university education or equivalent.
They must be able to demonstrate their commitment to the Islamic Republic and the Supreme Leader and to Islam (unless they belong to a minority religion).
Nearly 40% of the original 7,597 candidates who registered were disqualified under an elaborate system that weeds out anyone believed to have an "unsuitable" political record of loyalty to the Islamic Republic.
Most of those who have been disqualified support political reforms. Some are former ministers and current Majlis deputies.
The minimum voting age was increased this year from 15 to 18 years. There are 43 million eligible voters in Iran.
What is the balance of power in parliament?
The current parliament is dominated by right-wing conservative and hard-line factions that control most of the state institutions and the main sections of the military.
The conservative groups oppose political reforms such as the liberalisation of the press and promotion of non-governmental organisations in Iran.
The opposition camp is made of pro-democracy reformist groups which have around 13% of the seats in the current parliament.
The outgoing Majlis also has 13 women and 41 clerics.
How does the system work?
Candidates must gain the majority of votes to win. They must also get at least 25% of the total votes cast in their respective province.
If they fail to reach the necessary percentage, voting goes into a second round where the candidate who receives the largest number of votes is declared the winner.
There are 45,000 election observers under the supervision of the Interior Ministry. Each political group is allowed two observers at every polling station. There are no foreign observers.
Election results for most constituencies are expected to be announced within 24 hours of the polls closing.
What are the main political groups?
There are three broad political categories - hard-line and traditional conservatives, reformists and centrists groups.
1. Hard-liners and traditional conservatives
These groups are referred to as principle-ists or fundamentalists - for their loyalty to the principles of the Islamic Revolution. There are two parallel coalitions in the group.
a) United Principle-ist Front (UPF)
UPF is the main pro-government group of conservative and hard-line politicians and has three main factions. The "Society of the Selfless Devotees of the Islamic Revolution" largely comprises former members of the Islamic Revolution Guards Corps. The "Followers of the Line of the Imam and Leadership" holds a majority within the present Majlis and "The Pleasant Scent of Servitude" faction has the closest links to the president.
b) Broad Principle-ist Front (BPF)
Some factions within this Front supported President Ahmadinejad in 2005, but distanced themselves from him because of his style of management and some policy issues. The BPF seek the patronage of former nuclear negotiator Ali Larijani. Other fringe groups in the BPF include the Islamic Iran Justice and Development Party which was formed from a Majlis faction that criticised government policy.
2. Left wing/reformist groups
These groups are referred to as Eslah-Talaban (reformists) or the Jebhe-ye Dovom-Khordad (23 May Front - in reference to the day former President Mohammad Khatami was elected in 1997). The reformists have two principal platforms:
a) National Trust Party and the Popular Coalition of Reforms (PCR)
The National Trust Party, a moderate pro-reform group, has been allowed to field candidates for about 55 per cent of the seats. The party is led by the former Majlis Speaker Mahdi Karrubi. Factions in the Popular Coalition of Reforms include the Moderation and Development Party and Mardom Salari (the Democracy party).
b) Coalition of Reformists
Up to 80% of the candidates from this pro-Khatami bloc are reported to have been disqualified. The group seeks political liberalization through political reforms at home, and a policy of detente abroad.
3. Centrist groups
The centre ground is relatively small. The main centrist party is the Development and Moderation Party which has reformist tendencies.
Q: What are the issues?
1. Foreign policy
The hard-liners support the government's anti-Western foreign policy. The UPF says it is against "all forms of foreign hegemony". It advocates "properly managed confrontation with American globalisation and Israeli state terrorism" and stresses support for the Palestinians.
The reformists generally advocate rapprochement with the West.
Iran holds 9% of world oil reserves but it has a high unemployment rate. Government figures say inflation is at about 15%.
Centrist factions are far more in favour of a free-market than both the left and right-wing groups. Centrists have called for Iran's integration into the global economy.
Right-wing groups have warned the opposition not to exploit public discontent over the economy.
3. Nuclear policy
The UN Security council wants Iran to suspend the enrichment of uranium and to stop construction of a heavy water reactor that could produce plutonium, a key ingredient for a nuclear bomb. But Iran says it is simply exercising its right to enrichment under the Nuclear Non-Proliferation Treaty.
Iran's nuclear policy is central to the hard-liners' political vision. The UPF feels that Iran's "successful" nuclear policy has "reduced foreign threats and opened a bright horizon for Islamic Iran".
The reformists are hoping to reap the benefits of public discontent with the government's nuclear programme. More radical reformists believe Iran should voluntarily suspend its uranium enrichment.
4. Women in politics
Iranian women activists complain that there are not enough women candidates. According to government figures, 8% of all registered candidates this year are women, compared to about 10% in 2004 elections and 6% in 2000.
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