By Sara Webb and Thomas Escritt

AMSTERDAM, Sept 26 (Reuters) - Dutch Prime Minister Mark

Rutte, 45, will need to be a political chameleon to pull off his

next act - forming a government.

In his last coalition, he had to juggle the interests of his

right-leaning Liberal Party and the centrist Christian Democrats

while bowing to the demands of anti-Islam, anti-immigration

politician Geert Wilders whose support he needed in parliament.

But after his party won the most seats in the election on

September 12, Rutte's next partner is likely to be the

centre-left Labour Party led by Diederik Samsom.

The two parties started formal coalition talks last Friday,

a process which typically lasts weeks or even months.

"You can ask, how can a politician work with the Christian

Democrats and Freedom Party and then with Labour," asks Hans van

Baalen, a Liberal Member of the European Parliament who worked

with Rutte on the executive committee in the 1990s.

"But he's easygoing like Ronald Reagan. He doesn't get

ruffled, he unites people."

Nicknamed the "teflon prime minister" because he manages to

avoid being tarnished by disasters, Rutte appeared unmoved even

when Wilders and his Freedom Party pulled the plug on his

18-month-old government in April by refusing to back budget

cuts.

When his government relied on Wilders' support, Rutte was

careful to distance himself from the populist politician's

anti-Islam views, while keeping Wilders sweet with promises to

introduce a ban on Muslim face veils and take a tougher stance

on immigration. But after Wilders brought down the government,

those policies were quietly dropped.





"A KILLER"

Rutte regularly tops opinion polls for the most popular

politician in the Netherlands. But behind the 24/7 smile and

calm manner is a career politician with killer instincts.

"It's impossible to dislike him, even after losing to him.

He's not a friendly guy, but he is likeable," said Kay van de

Linde, a political strategist.

Rutte has spent most of his life in politics - as president

of the young liberals, as a junior minister of Social Affairs

and Education - with a stint working in the private sector at

Unilever's peanut butter unit.

When he ran for the Liberal Party leadership against Rita

Verdonk in 2006, he caught his opponent by surprise.

"I thought he didn't have a chance," said van de Linde, who

was Verdonk's spin doctor. "He looked like a nice guy with

unkempt hair and large nerdy glasses. But he's a killer. He

destroyed (Verdonk) in an election, to my own shock."

Despite losing out, Verdonk - known for her tough views on

immigration - remained a popular figure with some party

supporters. She represented the party's right wing, adopting an

anti-Muslim agenda after the murder of Pim Fortuyn, who had

shaken up Dutch politics by criticising Muslim immigration.

But she frequently criticised Rutte's leadership,

eventually prompting Rutte to expel her from the party.

"At the time he represented the party's liberal wing, she

was the conservative wing," said van de Linde. "By expelling

her, he risked splitting the party - but it was the beginning of

his consolidation of power."

During this month's election campaign, Rutte warned voters

that a victory for his Labour opponents would be "dangerous" for

the Netherlands - even though in televised election debates both

party leaders engaged quite amicably, prompting speculation they

could be coalition partners. Within days, Rutte and Samsom had

started power-sharing talks.

"He surprised everyone, not just in the Netherlands but

across Europe. I suspect a lot of politicians (in Europe) are

calling him and asking him how he did it," said van de Linde.





GROOMED MANAGER

Under Rutte, the Liberals won the largest number of seats in

their history, making him one of the few European leaders to be

re-elected during the euro zone crisis. Part of that success may

have come from the managerial skills he learned at Unilever and

his ability to build a strong team of advisers and supporters.

Even though Liberals and Labour have governed together in

the past, both will have to be pragmatic and make concessions to

address crucial reforms in the housing and labour markets.

The two parties are more closely aligned on the euro crisis;

Rutte's support for bailing out Greece once prompted Wilders to

say "that man dreams in Greek, speaks Greek and eats Greek".

Usually the result of coalition talks is a formal contract

the size of a telephone directory.

"It's a very detailed document. It spells out the

legislation, foreign policy priorities, everything you need to

have a basis on which to govern," said Lousewies van der Laan,

the former head of social liberal party D66.

"It's a killer pre-nuptial agreement."

But some politicians say Rutte could choose to form a

coalition based on trust between himself and Labour's Samsom,

giving parliament a greater role in setting policy.

Both men share a deep interest in American politics and in

helping the disadvantaged. Samsom worked as a "street coach",

trying to keep unemployed youths off the street, while for the

past few years Rutte has taught current affairs for a couple of

hours a week at a school for immigrant children in The Hague.

While Rutte's youthfulness is part of his appeal, some

questioned the bachelor premier's leadership qualities when he

admitted a few years ago that his mother still did his laundry.

Politicians who know him say that criticism is misplaced:

Rutte's father died when he was still a young man and the prime

minister remains very close to his mother.

(Editing by Stephen Powell)