Some of these politicians will also be contesting for the presidency.
They say they want the elections delayed because there are problems that need to be resolved.
Sadiq al-Mahdi, a presidential candidate and head of the National Umma Party, said: "The elections must be postponed till November to ensure its credibility and honesty."
He said that the problems in the south and in the western Darfur province need to be tackled.
But the government says the call for delay shows that the opposition is weak.
Nafea Ali Nafea, an adviser to Omar al-Bashir, the Sudanese president, said: "The talk for postponing the election shows how weak these parties are … it's flirting [by] these parties [with] the Sudan People's Liberation Movement."
The opposition groups have accused Sudan's National Independent Election Commission of not living up to its name and showing pro-government bias.
They have called for another truly independent body to monitor the performance of the electoral commission, a demand already rejected by the government.
Regardless of the conflicting political demands, election date is fast approaching and, with it, a heated political climate that raises many fears and concerns.
Meanwhile, peace talks between the Khartoum government and the opposition Justice and Equality Movement (Jem) are continuing in Qatar.
A senior Jem official has cautioned that the negotiations will be "tough" and that they may not end conclusively by March 15, as envisaged by both sides.
Source: Al Jazeera