The SNP will be hoping the launch this afternoon of their general election campaign in Glasgow will help put the party on the front foot after the first full week of campaigning was overshadowed by the sanctioning of former health secretary Michael Matheson.

None of the main parties had a trouble free start to their campaigns over the past seven days with the Conservatives hit by internal discontent over Rishi Sunak's plan to introduce a form of national service for young people if his party is returned to power, while Labour faced anger over its treatment of long-serving left wing MP Diane Abbott and whether she should be allowed to stand again.

But it is perhaps the SNP that stand to lose most from a rocky beginning in their efforts to win voters' support, and to win back former supporters, some of whom are considering voting for Labour while still backing independence.

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At a UK level, polls suggest Labour has close to a 20 percentage point lead over the Conservatives indicating a strong likelihood that Sir Keir Starmer will be replacing Mr Sunak in Number Ten after polling day on July 4.

In Scotland the polls are considerably narrower among the two frontrunners, Labour and the SNP.

On Friday, a poll by Savanta found that Mr Swinney had managed to “stem the bleeding” of support from the SNP simply as "a likely consequence of him simply not being Humza Yousaf.”

However, that little bit of good news for the SNP has to be tempered by the finding that Sir Keir Starmer’s party was on 37%, putting them “within touching distance” of 30 seats in Scotland, while the SNP was on 33%. (The same poll put the Tories on 17% and the Lib Dems on 7%.)

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According to an analysis by Professor Sir John Curtice, on those figures, Labour would win 28 Scottish MPs, up from their current two, while the SNP would drop to just 18 seats (down from 43 currently and the 48 it won in 2019).

With the polls close between the SNP and Labour it makes sense in the election campaign for Mr Swinney to go on the offensive against Labour accusing the party of not really being that different from the Conservatives and that it is the SNP who would best represent and reflect Scotland's interests and values.

He told supporters and the party's candidates that voters want "rid of this disastrous, chaotic Tory government" but as he did so accused Labour of pursuing Conservative policies including Brexit, more privatisation of the NHS and austerity.

"I’m not saying Labour are exactly the same as the Tories. They’re not. But they are giving an awfully good impersonation of them," said Mr Swinney in a key part of his speech.

"Austerity from the Conservative Government has been a curse that is inflicting significant damage on the NHS, housing and other public services.

"Brexit alone has wiped billions from the Scottish economy compared with EU membership. And it’s pushed up food, mortgages, and other household costs. Labour knows all of this. Keir Starmer is an intelligent man. He knows this is the effect of austerity and Brexit. But he’s still willing to impose all that damage on Scotland – whatever the cost - so he can win power. I’m sorry – but that’s quite simply unforgivable."

There are still over four weeks to go before polling day. 

In that time the parties will launch their manifestos, leaders will take to the small screen in TV debates and events beyond the control of parties can happen to influence voters.

As today's SNP launch made clear Mr Swinney and his party will not want their campaign to be knocked off course again and that those independence supporters toying with backing Labour to oust the Conservatives from power can be persuaded to return to the fold.