Garrulous = talkative. Some who is very talkative is often referred to as being
garrulous. Bloviating is a from of being garrulous - when one is a longwinded
pompous windbag he is bloviating. He is also being garrulous at the same time by being overly talkative.
Most politicans are garrulous - overly talkative about little of importance - talking more about themselves.
Another term for someone who tends to be garrulous - is
popinjay. A popinjay is a person who talks way too much in a conceited manner.
I recently went to a political
fundraiser - for the most part the speakers were garrulous - way to
talkative with out saying anything substantive. There was more
bloviating taking place than important discussion. These garrulous windbags were being popinjays.