Ghana's presidential election race, which ends with a run-off on Thursday, has taken an ethnic turn with the two candidates targeting specific tribes in their struggle to succeed veteran President Jerry Rawlings.

Campaigners for opposition hopeful John Kufuor of the New Patriotic Party (NPP), who takes a first round lead of almost four percent into the run-off, have been targeting voters in Rawlings's Volta region stronghold.

Their message, in advertisements published in newspapers on Saturday, is that the poorer eastern region can ``end its (traditional) isolation'' by voting for Kufuor, who is a member of the country's once-dominant and traditionally wealthier Ashanti tribe to the west.

But campaigners for Kufuor's rival John Atta Mills, Rawlings's vice-president and anointed successor, have responded by highlighting the Ashanti roots of Kufuor's party -- suggesting that a vote for Kufuor will mean exclusion

Ghana, a former British colony in which gold and cocoa underpin a fragile economy, has remained an oasis of peace in a region racked by ethnic and political rivalry in the decade following the end of the Cold War.

Rawlings, a radical firebrand who staged two coups before embracing democratic and economic reform and the role of an elder statesman, is stepping down at the age of just 53 after serving two four-year terms allowed under the constitution.

His decision to respect the constitution echoes a decision by Senegal's veteran President Abdou Diouf to step down gracefully after losing an election last March -- a rare example in Africa of a peaceful switch of power through the ballot box.

Vote In Rawlings Stronghold Crucial

But the way that Rawlings's home Volta region votes will be crucial to the result of Thursday's run-off.

Almost 90 percent of voters there backed Mills in the December 7 first round, only slightly down on the 96 percent in the 1996 election.

The Ewes and the Anlos of the region still see the NDC as a Rawlings party, not least because he remains its founder and life-leader.

In the first round, when Kufuor won 48.35 percent of votes compared to Mills's 44.85 percent, the opposition made inroads among the Fantis in the south-west, Mills's home region.

Kufuor, a lawyer and businessman, won six of the country's 10 administrative districts in the first round. All the other five first round candidates have rallied behind him.

In a parliamentary election on December 7, the NPP opposition broke the NDC stranglehold on power, becoming the largest party in the new 200-seat parliament with 99 seats but falling short of an absolute majority.

Mills and the NDC have hit back among the Fantis, urging them to vote for their kinsman. Mills himself spent several days campaigning in the south west last week.

With a helping hand from Rawlings himself, they are also targeting the Ga people of Accra and surrounding towns, where the opposition won extra support in the first round.

Rawlings has met Ga traditional authorities and urged them to rally behind Mills.

The first round was peaceful, except for violence in one flashpoint northern constituency where rivalry boiled over into ethnic clashes which killed 30 people.

But foreign observers reported the poll overall to be free and fair.