THE first poll of SNP members has given Humza Yousaf a narrow lead over Kate Forbes in the leadership contest.

However, the survey, carried out by Savanta for the Daily Telegraph shows around a third of the party have still to make up their minds. 

When asked who they would back in the contest, 31 per cent of members said Mr Yousaf while 25% backed Ms Forbes. Ash Regan was a distant third on 11%.

The remaining 32% answered don't know.

READ MORE: Yousaf's gay marriage vote excuse under spotlight as lawyer intervenes

With the don't knows removed, Mr Yousaf is on 46%, Ms Forbes on 37% and Ms Regan on 17%.

If that result is reflected when the ballot closes on March 27, then Mr Yousaf would fall short of a majority, and the race would then depend on the second preference of Ms Regan's voters. 

It seems likely most of those would break for the Finance Secretary.

According to the pollster, Ms Forbes' supporters are more likely to be male and older, with 33% of the over 55s giving her their first choice. Mr Yousaf's supporters are more likely to be younger, with the Health Secretary winning over 42% of the 18-54s.

Chris Hopkins, Political Research Director at Savanta said: “This first poll of SNP members really indicates that the race to replace Nicola Sturgeon is too close to call.

"While Humza Yousaf narrowly leads Kate Forbes, with such a high proportion of undecided voters, it’s difficult to be able to say definitively who is really in the lead.”

“There is a small indication that undecided voters may break for Yousaf, with male members more likely to break for Forbes, and women making up a higher proportion of undecided voters at the moment, but it’s also hard to know for sure to what extent gender is a key driver for vote intention among SNP members."

READ MORE: Councils and government make new pay offer to teachers

Mr Hopkins added: “Removing undecided voters to give a headline voting intention still puts Yousaf short of the 50% threshold required, and therefore he would require some of Ash Regan’s votes to transfer to him to be elected leader.

"It does appear from these figures that Ash Regan’s race is run, barring any major changes between now and the announcement, but where the second preferences of her supporters go could end up being pivotal in a race that, on this evidence, could go down to the wire.

“SNP members are, of course, difficult to poll, and it’s impossible to truly know their demographic make-up.

"However, using academic research into party membership in the UK that is available, it is possible to estimate how the SNP’s membership is comprised, and therefore this is a unique first look at what actual members who can vote in this leadership election think, rather than polls of SNP voters who do not have a say when electing the leader.” 

The poll comes ahead of the party's second hustings in Glenrothes.