San Francisco Frontiers - Scotland's new leader: the contenders

Here are the three contenders:

- Kate Forbes -

At just 32, Forbes would become one of the world's youngest political leaders if she wins.

She was first tipped for the SNP leadership in 2020 after stepping in to deliver the budget with only a few hours' notice, when finance minister Derek Mackay resigned unexpectedly.

Born in Dingwall in the Scottish Highlands, Forbes spent her childhood at a Gaelic-language school in Scotland as well as in India, where her parents worked as missionaries.

Forbes worked as a chartered accountant for Barclays in London before returning to Scotland, becoming a member of the Scottish parliament (MSP) in 2016.

Forbes, a member of the conservative Free Church of Scotland, got off to a rocky start by saying she would have opposed same-sex marriage had she been an MSP.

That put her strongly out of line with the SNP's centre-left base and lost her support, although she pledged to "defend to the hilt everybody's rights".

Forbes has called for a new generation to lead the SNP, saying that "more of the same is not a manifesto -- it is an acceptance of mediocrity".

She also said not enough groundwork had been done to prepare for independence.

- Humza Yousaf -

Yousaf, 37, has been endorsed by more MSPs and MPs than his two rivals and is considered the frontrunner and preferred candidate to succeed Nicola Sturgeon.

His supporters hail him as a polished communicator who can unite the party.

Yousaf has served in the Scottish government since 2012 in various roles including justice, transport and latterly health.

He was elected to the Scottish Parliament in 2011, taking his oath in English and in Urdu.

His close ties with Sturgeon make him the continuity candidate and the one who would aim to maintain the power-sharing agreement with the Scottish Greens.

Yousaf, who is Muslim, has vowed to challenge the UK government's block on controversial gender recognition legislation.

He also argues that independence can only be won by pushing progressive values and wants the SNP to talk more about the vision for independence than the mechanism, to appeal to floating voters.

Yousaf, however, has his own political problems from mounting issues in Scottish healthcare on his watch and from contentious hate crimes legislation he pushed as justice minister.

If Yousaf wins, he will be the first ethnic minority leader of a devolved government and the first Muslim to lead a major UK party.

- Ash Regan -

Though she was a government minister for four years, Regan, 49, was relatively unknown outside the Scottish Parliament until she resigned over the Sturgeon-led government's proposed gender recognition law.

Regan has accused her opponents of being "wishy-washy" on independence and has pledged to unite "Yes" groups and political parties through an independence convention.

She has proposed treating every election as a vote on independence, wants to introduce a separate currency if Scotland does so and has even produced mock-ups of what the new money will look like.

Regan worked in public relations, marketing and event management in England before returning to Scotland to join a pro-independence think-tank.

She was a prominent member of the Women for Independence movement and joined the SNP after the 2014 referendum, becoming an MSP in 2016.

Sturgeon appointed her community safety minister two years later.

L.Lopez--SFF