* No presidential hopeful can claim sweep by party
* Uncertainty rises about presidential race
* Independents expected to win in regions
* Moderate leftist leading Lima's vote for mayor
* Ruling party seen being trounced
By Marco Aquino and Teresa Cespedes
LIMA, Oct 4 (Reuters) - A diverse lot of political outsiders were handing traditional parties a stinging defeat in Peru's regional elections, partial tallies showed on Monday, suggesting the country's presidential vote in April will be more unpredictable than expected.
The parties of each of the four leading presidential candidates had weak showings or no showings at all in Peru's 25 governor races -- two-thirds of which were expected to be won by tiny parties with names like the Regional Alliance Together for the Amazon.
Political analysts said if the early results from Sunday's voting hold, they would show that traditional parties -- and perhaps their presidential candidates -- are struggling to tap into voters' needs in one of the world's fastest-growing economies.
In the capital of Lima, where a third of voters reside, Susana Villaran, 61, a moderate leftist who says she favors private investment, was expected to eke out a victory in the race for mayor, which has not been won by a left-wing candidate in three decades.
With 65 percent of the municipal vote counted, Villaran, who needs a plurality to win, had 38.7 of the vote, nearly two percentage points more than conservative candidate Lourdes Flores.
The APRA party of President Alan Garcia, who cannot run for a second consecutive term, was in a neck-and-neck race to win just one of the 21 governors races for which it fielded candidates, early results showed.
Garcia's approval rating hovers near just 30 percent. Conflicts over natural resources and poverty in remote regions have at times tarnished the luster of an economy that has surged on his watch. Garcia's party has had a tough time settling on a presidential candidate.
"Peruvians want renewal. They are tired of the same political faces," said Manuel Saavedra of local pollster CPI.
He said that while the presidential race over the next six months might be unpredictable, it was unlikely that voters would ultimately back a candidate bent on rolling back market-friendly policies that have helped the economy boom.
"I don't think any radical candidate will have a chance in 2011," Saavedra said.
PARTIES OF PRESIDENTIAL CANDIDATES LOOK WEAK
Ollanta Humala, a left-wing ultranationalist who unnerved financial markets when he nearly won the 2006 presidential contest, is now in fourth-place for next year's vote.
Allies of his Nationalist Party were forecast to win just two governors races -- in Cusco and Arequipa, where voters have long tussled with leaders in Lima.
Villaran's apparent victory probably will not help Humala and may even prompt her party to launch its own candidate, who could siphon away votes from Humala, analysts said.
Villaran has tried to distance herself from Humala by sharply criticizing his friends like Venezuelan President Hugo Chavez.
The other three candidates in the presidential race favor policies backed by investors -- low inflation, fiscal discipline, foreign investment and free trade.
The Fuerza 2011 party of presidential front-runner Keiko Fujimori, a conservative lawmaker and daughter of jailed former President Alberto Fujimori, was expected to win just one governors race and competed in relatively few races.
The parties of the two other main candidates in the presidential race -- Lima Mayor Luis Castaneda, in second place according to polls, and former President Alejandro Toledo, in third place -- were expected to come up empty handed in the governors races. Toledo's party fielded few candidates and Castaneda's party none at all.
Agustin Figueroa, a political analyst, said the national political scene was looking more unpredictable -- a trend that could pose difficulties for presidential and congressional politics.
"We are seeing a new mosaic in the regions, different from the previous one," he said. "It's new but is totally divided." (Additional reporting by Emily Schmall; Writing by Terry Wade; Editing by Stuart Grudgings and Bill Trott)