The finance secretary said yesterday that her conscience would not have allowed her to vote in favour of same-sex marriage, which passed in Holyrood in 2014, if she had been an MSP at the time.
Ms Forbes, health secretary Humza Yousaf and former community safety minister Ash Regan are running to replace Ms Sturgeon as SNP leader and First Minister following her resignation.
The finance secretary, a member of the Free Church of Scotland, was asked on BBC Radio’s Good Morning Scotland programme if her campaign was over before it began.
She replied: “Absolutely not. We have a large party membership, most of whom are not on Twitter. I understand people have very strong views on these matters. I think the public are longing for politicians to answer straight questions with straight answers and that’s certainly what I’ve tried to do in the media yesterday. My position on these matters is that I will defend to the hilt everybody’s rights in a pluralistic and tolerant society, to live and to love free of harassment and fear.”
Ms Forbes later said she regrets the pain caused by her comments. On Times Radio, she said: “I regret enormously the pain or hurt that has been caused because that was neither my intention, and I would seek forgiveness if that is how it’s come across.”
Meanwhile, Mr Yousaf has said he will “always fight for the equal rights of others”.
Asked what he thought of what Ms Forbes had to say on same-sex marriage, he told the Good Morning Scotland programme: “It’s for her to defend her views, I’ve made my views very clear.”