Prince Johnson revelled in sweet revenge after capturing Liberian President Samuel Doe in 1990, celebrating with cans of Budweiser as his fighters mutilated the toppled leader before executing him.

More than 20 years on, Johnson has a new chance to shape his civil war-scarred West African country -- not as a fighter, but as a politician whose strong support could give him the unlikely power to pick the next president.

Liberian voters head to the polls on November 8 to choose between incumbent President Ellen Johnson-Sirleaf and her rival Winston Tubman. And Johnson's support could deliver as much as 10 percent of the country's votes.

Johnson said he is hashing out an endorsement deal with Johnson-Sirleaf, a newly-named Nobel peace laureate, and has asked that his party take 30 percent of her government if she accepts his backing and wins re-election.

It could prove a bitter pill for Johnson-Sirleaf and Liberia's international partners to swallow.

Obviously Prince Johnson's track record is tainted, but in politics you get strange bedfellows, said Joe Pemagbi of the Open Society Initiative for West Africa.

I hope that whatever alliances are formed will contribute to reconciliation and unity in the country.

Analysts have said Johnson's rise in Liberian politics after 14-years of conflict killed nearly a quarter of a million people, could force donors like the United States and the European Union into the tough position of weighing peace, stability and democracy against the need for justice and an end to impunity.

The stakes are also high for investors who are preparing to pour billions of dollars into the country's mining projects.

But a prominent role in government could bring Johnson a step closer to his personal goal of transforming his legacy from that of a war monger to freedom fighter turned civil servant.

It is possible to draw a thick line under the past and move on, said Jolyon Ford of Oxford Analytica. What incentive for anyone to reform if they're never given credit for it?

HE'S GOT THE VOTES

Johnson took more than 11 percent of the ballots in Liberia's first round election on October 11, nearly all of them from his home county of Nimba, putting him in third place behind Johnson-Sirleaf and Tubman for the presidency.

It is in Nimba, perhaps the only place in the world, Johnson does not suffer a massive image problem: There he is a hero and a saviour, not a cold-blooded killer.

When people talk about warlords, I always ask: What is the meaning of warlord? Because you fought for liberation? he told Reuters in a recent interview. Can we say the Americans who fought in the American Civil War are warlords?

Johnson's formal military career with the Armed Forces of Liberia ended the 1980s after a failed coup against Doe's regime was orchestrated by a fellow Guio tribesman from Nimba.

Johnson fled into exile and watched from abroad as Doe's forces repeatedly attacked ethnic Guio and Mano villages in Nimba County over the next several years.

He returned to Liberia in 1989 as a rebel seeking vengeance, initially as part of Charles Taylor's infamous band of fighters and later as head of his own group, and in 1990 took control of most of the capital Monrovia to oust Doe.

Liberia's Truth and Reconciliation Commission named Johnson among those recommended for prosecution for war crimes, and said his group committed rape and killings.

A video of Johnson looking on as his fighters sliced Doe's ear off with a knife has since gone viral on the Internet -- a fact Johnson says he regrets.

Johnson fled again into exile after rebel forces merged under Taylor following Doe's execution. He turned to Christianity during exile, sought to reconcile with Doe's family and only came back to Liberia after fighting ended.

His supporters in Nimba County, grateful for his putting an end to Doe's rule, overwhelmingly elected him to Liberia's senate in 2005, the year Johnson-Sirleaf became Africa's first freely-elected female head of state.

Johnson said he is now throwing his support behind Johnson-Sirleaf because she is the lesser of two evils when compared with Tubman, adding he wants an overhaul of mineral revenue distribution alongside the stake in government.

He is an embarrassing ally, especially after Ellen Johnson-Sirleaf won the Nobel Prize for Peace, said Lydie Boka of risk consultancy StrategiCo.

Prince Johnson is not exactly associated with peace. And to give him 30 percent of government would be outrageous.

Johnson-Sirleaf's political party, UP, has said it welcomes the support from Johnson and other former warlords, and says it is proof the incumbent leader has what it takes to reunite the war-torn country.

Both Johnson and Johnson-Sirleaf, who won the Nobel prize this month despite admitting to having provided early support to Taylor's rebels, have both been named by Liberia's Truth and Reconciliation Commission as people who should be barred from political office for their roles in the conflict.

But the government has not implemented the proposals.

(Writing by Richard Valdmanis; Editing by Sophie Hares)