FACTBOX: Pakistan's legislative elections

(Reuters) - Pakistan holds elections for the lower house of parliament and assemblies in its four provinces on Monday. The elections were postponed from January 8 after the assassination of opposition leader Benazir Bhutto on December 27.

Following are some facts about the elections:

* The election is for 272 National Assembly seats. Another 70 seats in the 342-seat National Assembly are reserved for non-Muslims (10) and women (60), which are allocated to parties according to how many votes they win.

* Seats are allocated on the basis of population. Of the 272 National Assembly seats, 148 are in Punjab province, 61 in Sindh, 35 in North West Frontier, 14 in Baluchistan, 12 in the Federally Administered Tribal Areas and 2 in the capital, Islamabad.

* There are about 81 million registered voters.

* Members of the assemblies are elected by secret ballot in direct voting in a constituency in a first-past-the-post system.

* The voting age is 18.

* Polls will open at 8 a.m. (10 p.m. Sunday EST) and close at 5 p.m. (7 a.m. EST).

* Turnout in the last general election in 2002 was 41.7 percent. Analysts say turnout on Monday could be hurt by fears of violence.

* The main parties contesting the election are: the Pakistan Muslim League (PML), sometimes called the PML-Q or Q League, which backs President Pervez Musharraf; the Pakistan People's Party (PPP) of assassinated former prime minister Benazir Bhutto; and the Pakistan Muslim League (Nawaz) of former Prime Minister Nawaz Sharif, also known as the PML-N or Nawaz League.

* It is not a presidential election, but President Pervez Musharraf's future could be at stake if voters return a hostile parliament. Musharraf's foes say his re-election for a second five-year term by outgoing assemblies last October was unconstitutional, and they could move for his impeachment.

* In the last parliament, the PML controlled 130 seats, the National Alliance, which later became part of the PML, had 16, and the party of Aftab Ahmed Khan Sherpao, interior minister in the PML-led coalition, held 19. The PPP held 63, a six-party Islamist alliance called Muttahida Majli-e-Amal (MMA) held 59, the PML-N had 18, a pro-Musharraf regional party in Sindh province called Muttahida Qaumi Movement (MQM) held 18, and minor parties and independents accounted for the other 19.

(Writing by Robert Birsel; Editing by Jeremy Laurence)