Pro-Basque independence parties are poised to win seats in Spain's parliament in general elections Sunday for the first time in 15 years, boosted by ETA's decision to lay down arms.

The armed Basque separatist group announced on October 20 -- exactly a month before the election -- the end of its 40-year campaign, blamed for 829 deaths, of bombing and shooting to create a Basque homeland.

The move has fueled support for pro-Basque independence coalition Amaiur and three other separatist parties, which pollsters predict may win between three and five seats in Spain's parliament.

"For the first time in years we are able to join our forces and go to Madrid to say that we are a people and we want to form our own state," 46-year-old teacher Marije Fullaondo said at a Amaiur rally in San Sebastian on Saturday.

"Independence! Independence!," the crowd of some 10,000 people chanted at the rally.

Winning seats in parliament would be a breakthrough for the Basque independence movement, seeking to defend its goals at the ballot box where it can take advantage of an electoral system that favours the representation of regional parties.

"This is a key moment for the defence of sovereignty," said Amaiur candidate Inaki Antiguedad, who recalled how another pro-independence coalition, Bildu, performed strongly in local elections in May.

Bildu, which was also banned by Spanish courts over its alleged links to ETA, became the second-strongest political force in the Basque region, which is home to 2.2 million people, a result Antiguedad called a "political tsunami".

If elected, he said he will push in parliament for a referendum on Basque self-determination.

"We want for the Basque Country exactly the same amount of sovereignty which European states currently enjoy," he said.

Joseba Alvarez, a veteran leader of ETA's political wing Batasuna which has been banned since 2003, said this goal "would take several years and require a lot of work", adding only one-third of Basques back independence.

Basque independence groups last won representation in Spain's national parliament in 1996 when Batasuna's predecessor, Herri Batasuna, won two seats in the assembly.

But the participation of Basque separatists in debates in Spain' parliament will still be a novelty.

While Herri Batasuna regularly won a handful of seats in parliament in the 1980s and 1990s, its lawmakers boycotted the assembly arguing it was a Spanish state institution that they did not recognise.

If pro-Basque independence lawmakers are elected to parliament, they will occupy seats in an assembly dominated by the conservative Popular Party which strongly opposes giving any more powers to the regional Basque government.

Popular Party leader Mariano Rajoy has also flatly ruled out negotiating with ETA, which said last week that is may disarm but wants its roughly 700 prisoners in Spanish and French jails freed.

But Gorka Landaburu, director of magazine Cambio 16 and a Basque expert, said it will be difficult for Rajoy to ignore the outfit's offer.

"It is a topic which the next head of government will be pleased to address. It will give him the chance to say: 'With me we achieved ETA's definitive end," he said.

ETA last month vowed to stop using weapons in its drive for an independent Basque homeland but stopped short of saying it would disarm

The Popular Party enjoys a double digit lead over the ruling Socialists, who have been in power since 2004, and are tipped to win an absolute majority in Spain's 350-seat parliament.