• Conservative Party leader David Cameron and his pregnant wife Samantha visit the Children's Hospital in Birmingham yesterday ahead of the third and final leaders' debate. Picture: Getty
The broadcast comes as some activists have been privately grumbling about the lack of showing from Mr Cameron, who has only strayed into Scotland once since the election was called, while a new poll has suggested that the party could be facing another 1997-style wipe-out.
With just a week to go, Mr Cameron appealed to Scots reminding them that "this is the most important election in decades". He added: "It's one of those moments that our whole history will turn on a single day of destiny."
He said Scots had "a huge role to play" adding: "Every vote, every constituency, every Conservative MP matters". And he claimed that with more Conservative MPs "Scotland will have a stronger voice at Westminster".
His appeal comes as a poll of more than 1,000 Scots has put the Tories in at a mere 12 per cent in contrast to its growing support in England and Wales.
It is forth behind Labour on 41 per cent, the SNP on 22 per cent and Lib Dems on 20 per cent.
This could leave the Conservatives with no seats north of the Border, leading to a potential constitutional crisis if the party wins a majority in Westminster.
A party spokesman pointed out that only 7 per cent of those polled had backed the Tories in 2005, so the result in fact represented a 5 per cent gain.
He added: "Our private polling in our (11] target seats suggests that we are doing much better".
He said Mr Cameron, who had promised to come to Scotland three times during the campaign, had been stopped because of the volcanic ash crisis, but would visit again before polling day.
The positive message of the party political broadcast contrasted hugely with Labour's Scottish negative broadcast entitled: "Remember Scotland under the Tories".