Well-liked politician whose electoral achievements as leader of the Liberal Democrats were overshadowed by his personal trials

Charles Kennedy, who has died aged 55, led the Liberal Democrats in the elections of 2001 and 2005 to their highest number of seats since 1923, and on the eve of the invasion of Iraq in 2003 momentarily seemed in with a chance of forming a government; yet his six years as leader were overshadowed by criticism of his work rate, and rumours of a drink problem which – when confirmed – forced him out in January 2006.

A sandy-haired Highlander whose sense of humour went down well on television programmes like Have I Got News For You?, Kennedy was first elected to Parliament (for the SDP) as a 23-year-old student, and proved his mettle as president of the Liberal Democrats from 1990 to 1994.

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Succeeding Paddy Ashdown as leader in 1999, whose closeness to Labour he had consistently criticised, Kennedy repositioned the Lib Dems as the radical alternative to a struggling Tory opposition. The strategy Kennedy and his election co-ordinator Lord Rennard followed, of “targeting” seats, paid off with further gains, mainly from Labour as Tony Blair’s policies alienated the Left; attempts to “decapitate” leading Tories proved a failure.

Kennedy scented power in February 2003, as George W Bush prepared to invade Iraq. Blair moved to commit British forces, claiming Saddam Hussein had weapons of mass destruction that could be deployed against Britain at 45 minutes’ notice. Kennedy spoke strongly against an invasion, and, with many Labour MPs just as opposed, there was a chance that Blair would suffer a moral, if not numerical, defeat in the crucial debate – leading to a dissolution, or a government headed by opponents of war.

On February 26, 122 Labour MPs joined 77 from Opposition parties to support the motion that “This House finds the case for military action against Iraq as yet unproven”. Rebellion on this scale was unprecedented, but the margin was just enough for Blair to go ahead. It did, however, put Kennedy at the head of a body of opinion in the country which grew as the overthrow of Saddam – and failure to find the weapons – was followed by ongoing carnage.

After the inconclusive election of 2010, when Nick Clegg led the party into coalition with David Cameron’s Conservatives, Kennedy was the most vocal critic of the deal. And when Vince Cable announced that October that Lib-Dem ministers had abandoned the party’s pledge not to increase university tuition fees, he led rebels into the “no” lobby.

Blair may have enjoyed his tennis and William Hague his workouts, but Kennedy, a 40-a-day smoker, was averse to exercise; at university his nickname was “Taxi”. His one recreation, until his immersion in politics, was playing the fiddle. While no one doubted his ambition, his laid-back style aroused consistent criticism from hyperactive Liberals.

Voters will remember Charles Kennedy with affection

Charles Peter Kennedy was born in Inverness on November 25 1959, the younger son of Ian Kennedy, a crofter who became an engineer, and the former Mary MacEachen. Educated at Lochaber High School, Fort William, his instruction as a Catholic came from Roderick Wright, who would become Bishop of Argyll before eloping with a local divorcee.

Kennedy read Philosophy and Politics at Glasgow University, where he was President of the Union in 1980-81; Britain’s last all-male university Union, it began admitting women during Kennedy’s term. In 1982 he won the Observer Mace for debating.

He worked briefly for the BBC in Inverness before taking up a Fulbright scholarship at the University of Indiana. While he was there the SDP selected him for Ross, Cromarty and Skye – the 1983 election ensuing before his course was finished.

He flew home and defeated the Conservative energy minister Hamish Gray by 1,704 votes to become “baby of the House”. Kennedy was the only SDP candidate to gain a seat (and one of only six elected) as its joint campaign with the Liberals failed to parlay votes into seats; even in 2005, Kennedy’s Lib Dems polled a smaller share of the vote than the Alliance parties in 1983.

Kennedy would hold his seat with increasing comfort through subsequent general elections, representing in turn Ross, Skye and Inverness West and Ross, Skye and Lochaber; he was defeated there last month by the SNP’s Ian Blackford, falling victim both to the anti-Lib Dem stampede and to the SNP’s rout of all other parties in Scotland. He was the last member of the Commons to have been elected as a Social Democrat.

Kennedy's maiden speech in the Commons, 1983

At Westminster he became the SDP spokesman on health, social services and Scottish affairs. In this last capacity he called on the secretary of state, George Younger, with Roy Jenkins, whose speeches he had been studying only weeks before, at Dover House – sitting open-mouthed as Jenkins expatiated on the former occupants whose portraits lined the walls.

Kennedy admitted his inexperience when, deputed to speak on the rate support grant, he confided to a colleague: “I have never paid rates in my life.” But he was a quick learner, criticising “Tory meanness” over social security, warning that the NHS was “no longer the best in the world” and voicing concern that Soviet spies could slip into Britain through Ullapool, where there was no immigration control despite 47 Eastern bloc vessels lying at anchor.

Before the 1987 election, Kennedy warned Social Democrats and Liberals that there was “an inescapable duty on any party aspiring to government to advance sensible and sound defence policies”. The Alliance again failed to break through after a campaign he branded “a massive turn-off”.

When David Steel reacted by proposing a merger of the parties, Kennedy was the SDP’s only MP to back him. When David Owen resigned as SDP leader, Kennedy nominated Robert Maclennan, who had come round to supporting a merger. At the SDP conference, his motion advocating a single party was carried on a show of hands.

With Maclennan, Kennedy called on Owen to urge him to come on board, only to be shown the door. He stood firm against SDPers who wanted to change the new party’s name to the Alliance. He backed Steel to lead it, then served under Ashdown as trade and industry spokesman.

As Ashdown began to rebuild the party’s battered poll ratings, Kennedy was named “Member to watch” by the Spectator. After the continuing SDP’s defeat by the Official Monster Raving Loony Party at Bootle in 1990, he again invited Owen “back to the fold”. Again he was rebuffed.

Kennedy was elected president of the Liberal Democrats that August. He adopted a campaigning role, telling the next year’s conference that while Labour was the party of dire straits and the Tories of simple minds, “we are the new kids on the block”.

The 1992 election put a floor under the Lib Dems, Ashdown delivering 20 seats, an improvement despite the intervening dramas which had alienated much support. Kennedy became spokesman on Europe and East-West relations; the former put him in the limelight as John Major struggled to get the Maastricht Treaty through Parliament.

An ardent European, Kennedy came under strong pressure from Labour to join with them and Tory Eurosceptics to defeat the government. In the event the Lib Dems voted with Labour on points of detail, but backed the government when the treaty seemed at risk of defeat.

Kennedy presented Radio 2’s Jimmy Young Show for a week, then chaired Carlton Television’s A Kick in the Ballots. But it was his appearances on Have I Got News for You? – which he would become the first party leader to host – that made him a household name.

His party’s fortunes were improving, too – winning by-elections and making heavy gains from the Conservatives in the 1994 council elections. But a week later the Labour leader John Smith died, and the initiative passed to his successor Tony Blair.

Appreciating this, Kennedy backed the Lib Dems at 50 to 1 to win just two seats at the subsequent Euro-elections against the 11 predicted; when he pocketed £2,500, colleagues were unimpressed. That September he stepped down as party president, reporting rising membership and Lib Dem control of nearly 40 councils.

As a constituency MP, he helped secure a reprieve for the Fort William sleeper as the railways were privatised, and boycotted the opening of the Skye Bridge in protest at the tolls. Nationally, he warned the party not to get too close to Blair as 1997 approached; Ashdown ignored him.

When, after Labour’s landslide victory and the Lib Dems’ gain of 26 seats, Ashdown took the party into a Cabinet committee with Blair, Kennedy, now agriculture spokesman, called for its remit to be confined to constitutional reform.

At the start of 1999 Ashdown announced his impending retirement. A lengthy leadership contest ensued, during which Kennedy cast New Labour as “bossy and authoritarian” and Simon Hughes’ supporters claimed their man would be more energetic. On August 9 1999 Kennedy defeated Hughes by 57 per cent of party members to 43. He was made a privy counsellor.

Kennedy began developing a radical agenda with calls for a Royal Commission on the legalisation of cannabis and tighter controls on genetically modified crop trials. He agreed to extend the Cabinet committee’s remit to cover EU reform, but after the 2001 election – in which six more seats were gained and the Lib Dem share of the poll rose to 18.3 per cent – ties with the government were cut.

Blair’s failure to implement proportional representation for Westminster elections proved to Kennedy there was little worth talking to Labour about, an impression deepened by the prime minister’s equivocation over the euro.

Kennedy told the Lib Dems’ 2001 conference that they could now “live a little dangerously”, and work to supplant the still-becalmed Tories as the main opposition. After the terrorist attacks of September 11, he urged a “cautionary hand” on America in its quest to defeat al-Qaeda. Between then and the invasion of Iraq, he positioned the Lib Dems as the only major party opposed to Bush’s attempts to identify as enemies a wide range of forces in the Islamic world, some unconnected with terrorism.

In the run-up to the war, concerns over Kennedy’s drinking first surfaced. Jeremy Paxman sparked a storm of protest by asserting, on air, that the Lib Dem leader was often drunk and asking him if he drank “a bottle of whisky, late at night”. Kennedy denied it, but the rumours persisted; he missed a debate on Iraq and one Budget through “ill-health”, and stumbled through the launch of his party’s 2005 election manifesto (though this could be explained by lack of sleep following the birth of his son Donald).

Kennedy’s stand on Iraq led the Lib Dems to further gains. They won 62 seats and 22.1 per cent of the vote, scoring some remarkable wins over Labour, notably in inner north London, as angry Labour voters changed allegiance. The much-publicised aim of “decapitating” the Tories claimed only one shadow education minister.

Kennedy's 2015 general election concession speech

Nevertheless, dissatisfaction continued over Kennedy’s performance. Sensing trouble, he called an immediate leadership vote and was re-elected unopposed. But after Cameron’s election that December to lead the Conservatives, senior colleagues told Kennedy he must “raise his game”. A “Kennedy must go” petition was circulated, and 23 MPs signed a letter rejecting his leadership.

Informed that ITN would report that he had received treatment for a problem with alcohol, Kennedy admitted that for 18 months he had been coming to terms with a drinking habit – but insisted he had been dry for two months. He called a further ballot, declaring himself a candidate, but after an ultimatum from 19 frontbenchers, with even some supporters saying he should go, he resigned on January 7 2006.

Kennedy gave his successor Menzies Campbell full support, and resumed campaigning and his television work. When Campbell resigned in 2007 – being replaced by Clegg – Kennedy said it was “highly unlikely” he would seek the leadership again. He remained an active speaker in the House, particularly on Europe, and in 2007 became president of the European Movement, a post vacant since the death of Sir Edward Heath. In 2008 he was elected Rector of Glasgow University.

In April his 88-year-old father, Ian, for whom he had been caring, died.

Charles Kennedy married Sarah Gurling in 2002; the marriage was dissolved and he is survived by their son.

Charles Kennedy, born November 25 1959, died June 1 2015