By Belén Carreño, Andrei Khalip

MADRID (Reuters) -Pedro Sanchez's reputation as a risk-taker precedes him, but a snap national election he has called for this month represents the Spanish prime minister's biggest political gamble yet.

The bold move, made in late May after his Socialist Party (PSOE) did badly in local ballots, took senior members of the party by surprise, according to sources.

PSOE's standing in opinion polls has improved since then, but as the election campaign got under way on Thursday, most surveys still showed the governing leftist coalition lagging the parties of the right.

The youthful-looking 51-year-old Sanchez, known as "El Guapo" (Mr. Handsome), made the call to bring the election forward from late 2023 to July 23 after the PSOE shipped votes to the mainstream conservative People's Party (PP) and far-right Vox.

The switch of date came just a month before Spain took over the rotating EU presidency on July 1, which Sanchez kicked off in Ukraine in a show of support for the country fighting off a Russian invasion.

"Pedro Sanchez is a gambler, and this is a bet with the only possible goal of minimising potential losses" the Socialists would have ceded to the right by year-end, political scientist Pablo Simon of the Carlos III University said in late May.

With polls showing the PP would almost certainly need to enter a coalition with Vox to get a parliamentary majority, Sanchez's strategy also involves rallying support by raising the spectre of a first far-right party in government since dictator Francisco Franco died in 1975.

An increased charm offensive is also on his list of priorities, exploiting the self-declared dullness of his main rival, PP leader Alberto Nunez Feijoo and criticising his reluctance to take part in all but one televised debate.

In television interviews over the past week, Sanchez went out of his way to demonstrate his more personal side, winning praise even from conservative media.

Interacting with a pair of puppets on an Antena 3 show, Sanchez, wearing an LGBT Pride wristband, was asked what he would tell his daughter if she fell in love with a Vox voter. "Love is free," he replied with a smile, provoking applause.

SNAP ELECTION WINS

Often underestimated by his opponents and sometimes by his supporters, Sanchez gained a reputation for doggedness when, as opposition leader in 2016, he stuck to his "no means no" mantra against enabling a conservative government.

The move laid bare divisions within PSOE after most other party members abstained to avert the need for another snap election after Sanchez lost two in as many years, and he was briefly ousted before returning as leader with backing from the party's grassroots members.

In 2018, he became the first politician in Spain to topple a sitting government via a no-confidence motion, taking over as prime minister and then winning two subsequent snap elections, ultimately forming a coalition government with the far-left Podemos, also a first.

He published a book, "Manual of Resistance", about his experience, in which he wrote: "It might sound presumptuous, but I realise that I grow in difficult situations".

Most of his term has been marked by crisis management.

Spain entered the pandemic with some of the world's highest COVID-19 mortality rates but then showed a spectacular recovery as the government applied tough restrictions, opened more hospitals and hired extra medical staff.

The economy suffered a record slump in 2020, but posted a solid rebound in 2021-22 thanks mainly to billions in EU rescue funds, of which Spain is one of the main recipients. After peaking at nearly 11% a year ago, inflation slowed to below 2% in June, one of the lowest levels in Europe.

Forced to tackle the politically disruptive consequences of a failed 2017 bid for independence by Catalonia, Sanchez's government tried to appease the separatists to get their support in parliament.

The opposition labelled him a traitor after he pardoned jailed pro-independence leaders and downgraded the crime of secession.

Passionately pro-European and integrationist, having studied economic policy in Brussels and worked in the European Parliament and the United Nations, Sanchez also sought to tackle another polarising national legacy.

The government exhumed Franco from his mausoleum, and promoted the search and exhumations from mass graves of victims of the civil war that preceded his 1939-1975 fascist dictatorship. It also removed Franco-era symbols from Spanish streets.

Under Sanchez's leadership, the PSOE, which he joined at 21, has suffered the fate of many of its left-wing and centrist peers across Europe, where traditional political identities have been undermined by populist leaders from across the political spectrum, notably the far-right, whose Spanish incarnation is Vox.

A basketball fan, Sanchez is married to a marketing professional and is father to two daughters.

(Writing by Andrei Khalip; editing by John Stonestreet)