South Africa's governing African National Congress (ANC) has failed in a legal bid to stop a newly formed party, backed by ex-President Jacob Zuma, from running in May's general election.
The uMkhonto we Sizwe (MK) party takes its name from the now-disbanded armed wing of the ANC.
It is thought that Mr Zuma's backing of the MK could affect the ANC's support.
The electoral court rejected the ANC's argument that the party had not met the official registration criteria.
Supporters of MK, dressed in green, danced in celebration outside the court after the ruling was read out.
The ANC has said it accepts the decision and will comply with it.
In a written statement, a spokesman said that this had not been about the ANC pursuing a case against the MK.
The party, he added, was not opposed to the MK's presence on the ballot, provided the registration conducted by the electoral commission was in accordance with the law.
The ANC has also instigated separate legal proceedings against the MK party, accusing it of copyright infringement.
Some opinion polls are predicting that the ANC 's vote share could fall below 50% for the first time in three decades in the 29 May election.
Mr Zuma appears to be drawing some support away from the party that has governed the country since 1994, especially in his home province of KwaZulu-Natal.
He did not found the MK party, but threw his weight behind it in December and has since been suspended from the ANC.
Mr Zuma once served in the ANC's MK, which was formed to help in the fight against apartheid and white-minority rule. He was South Africa's president for nine years from 2009, but forced from power and replaced by current President Cyril Ramaphosa in part over corruption allegations, which Mr Zuma denies.
Following his backing of the MK party, the ANC accused Mr Zuma of debasing the "proud history of armed struggle against the apartheid regime" through the "opportunistic use of military symbolism".
It also said the MK only exists to "erode the support base of the ANC".
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