how do folks make money blogging? Do they> can regular folks like me
make money blogging on topics we have strong interest, expertise or
opinion???

If you did make money blogging the first step is achieving popularity
with your blog (think about it, your competing will millions of other
bloggers out there so it better be exceptional). Unless you are
selling something through your blog, the best advice I can give is to
have advertising companies pay you to put ads on your blog. The
advertisements should be appropriate to the topics discussed or
emphasised in your blog. You would also have to check out the legal
rules of advertising if you are using a blog site. It would probably
be best to have your own server or hosted server which legally allows
for you to make a profit through advertising from your site. Always
check the laws if you have a unique idea of how to make money, you
don't want to get into a legal mess.

Yes you can earn by blogging.  First of all you should understand that
there is no free money.

There is a blog site called http://www.blogit.com.  It is a paid site.
 Your earning would be based on the following:



How Earnings Are Calculated
Writers earn money from each reader who reads their work. For example,
if Jack reads Jill's blog 20% of the time, Jill will receive 20% of
Jack's monthly payment to writers. (Learn more about how payments are
distributed)

Payment Distribution
Every month, Blogit keeps track of the number of times you read each
writer. At the end of the month, Blogit divides your writer payment
between all of the writers, based on how often you read each one.
As a simple example, say you only read Jack during the month. At the
end of the month, Blogit will send your entire writer payment to Jack.
Let's say you now start reading Jill half of the time, while still
reading Jack the rest of the time. In that case, Blogit will send half
your writer payment to Jill and the other half to Jack.
It's that easy. Since Blogit automatically does the math for you, you
can be sure each writer is receiving a fair share.
Notes
? Every page read is counted, so if you click on a blog and read five
pages of that blog, that is counted as five pages read.
? Comment pages are not counted.

This means that the writers who earn the most are the ones who
consistently post work of interest. Writers can even write multiple
blogs to appeal to different groups of readers.
Since a reader's subscription fee is divided between writers at the
end of the reader's monthly cycle, it may take up to two months for
writers to receive all of their earnings. (How do I withdraw my
earnings?)

The link for above:
http://www.blogit.com/Blogs/Help/HelpPage.aspx?page=earnings


Here you get the details of cost and the works:

http://www.blogit.com/Blogs/Help/HelpPage.aspx?page=billing


I have not joined to earn an referral commission from them (atually
they pay USD 20 for each subscription through a referral link.

You can join and enjoy making money.  But do they make???????

Put AdSense ads and you should be able to earn $1 per 100 visitors.