Scott Macnab: Televised debates could give the Labour and Lib Dem leaders a chance to shine against Salmond

THE impact of TV leadership debates transformed last year's UK election campaign, making a star of previously unknown Liberal Democrat leader Nick Clegg and helping bring about the first coalition government in a generation.

Such debates are nothing new in Scotland, but it will be interesting to see if they take on a new significance as the Holyrood campaign looms.

Three are planned so far and should be an opportunity for the two newcomers to the leadership arena, Labour's Iain Gray and Lib Dem chief Tavish Scott, to make their mark with Scots. Many still don't know who they are, but the debates will place them on a platform with First Minister Alex Salmond and in living rooms across the nation.

Gray has proved he can hold his own with Salmond in the weekly Holyrood joust at First Minister's Questions. Labour also believes the SNP leader could be undone by an Achilles' heel: his attention to detail – or lack of it. They feel Gray's ability to master and marshal facts could help swing things his way against the First Minister's tendency to rely on what they see as bluster and put-downs.

But Salmond, a former oil economist, is not renowned for making blunders, and it remains to be seen whether he will be caught out in this way. Nationalist insiders feel it is an opportunity laced with risk for the Labour leader. The more people know about Gray, they claim, the less they like him – and increased TV exposure will only magnify this. The chance to reach out to voters comes with the chance of a gaffe which can derail a campaign for days and leave parties effectively "firefighting" when they should be promoting policy.

Tavish Scott must be hoping that he can come through in the same way as his UK leader did last year, and Liberal Democrats feel that the exposure will only benefit the Shetland MSP. But he could face awkward questions over his party's role in the Coalition government cuts down south; and, for all Clegg's personal plaudits, the Lib Dems did actually lose seats.

Annabel Goldie is an adept debater both on TV and in the Holyrood chamber. She is also popular among voters, but the Tories' ongoing problem for years now has been how to translate this to votes come polling day.

One unknown quantity will be whether any impromptu alliances emerge when the cameras go on, after Gordon Brown's attempts to woo Clegg in the first debate last year had Lib Dem supporters chanting "I agree with Nick" for days afterwards.

Salmond often finds himself isolated on these occasions against the three unionist parties as debate invariably reverts back to the constitution. It will be interesting to see if the Tory-Lib Dem government down south will alter the dynamic of the Scottish clashes.

Could we even see an unlikely united front from Salmond and Gray as they set their sights on the Westminster Coalition partners over the cuts agenda?