I am no SEO expert. But what I read online, I understood that having https connection for your website helps. Google prefers content over secured connection than similar content with normal http connection.
I was checking if there is an option to get a free SSL certificate & install it for this domain using Blogger. And I found out that Blogger gives free SSL certificate for your blogspot blog which is hosted on custom domain.
You just need to go to Settings > Basic section from Blogger dashboard. Under “HTTPS” section, enable “HTTPS availability”. It took around 15 minute & within that time Blogger installed a free SSL certificate for my custom domain.
Once “HTTPS availability” status changed to available, I also enabled “HTTPS redirect” option. Now whenever a user will try to access this blog on http, he or she will be redirected to https connection. Also this redirect is a 301 redirect which will take care of old http pages that were already indexed in search engines like Google. Search engines should be able to understand that http pages have been permanently redirected to https pages.