Next Friday, April 21, is the final date for the money to be raised for the museum in memory of the two-time Formula One world champion.
At the beginning of this week, the amount raised stood at more than £200,000, with £71,725 pledged via the Jim Clark Museum crowdfunding site.
So far, more than 400 members of the public in 58 countries have contributed, and the trust has received direct donations of £180,00 from trusts and foundations, plus significant contributions from Jackie Stewart, John Clark, Morris Leslie and Boyd Tunnock.
Wider support has come from the local community of Duns in Scotland, corporate donations, car clubs, motorsport teams and champion drivers such as John Cleland and Louise Aitken-Walker.
The cost of the extension and remodelling of the Jim Clark Museum in Newtown Street, Duns, is £1.6m.
Scottish Borders Council has pledged £620,000 towards the museum, with a similar sum coming from the Heritage Lottery Fund, leaving £300,000 to be raised to make it a reality.
Doug Niven, cousin of Fife-born Clark, killed in a race accident in Germany in 1968, and a family trustee, said: “The outpouring of support to honour Jim’s legacy with this museum has been staggering, and getting the project to this stage would not have been possible without that support.
“Thanks to the generosity of the general public and private advocates of the museum, we are close to our target, but with the chequered flag approaching, we want to raise as much as possible to create a special place at Duns which will draw interest and visitors from around the globe.”
Donations to the Jim Clark Museum appeal can be made at www.crowdfunder.co.uk/jim-clark-museum ahead of the April 21 deadline.