Reputable bloggers with millions of subscribers do not often take up a developing project.
Literally anywhere you go just to advertise your project all what matter is the number of people who will see it because chances are a lot of them will be interested in what they are seeing, if the blogger has millions of viewers then definitely you will have some people interested of course it will be more if what the blogger is blogging about are related to what you are advertising. The way I see it is the effectiveness in advertising is always about numbers and how you can relate to the people seeing it.
It would actually depend on how that vlogger do able to deliver such advertisement clearly into its viewers.Interest and number of possible people would be hooked up
yet people do have different interest but with having a million subscribers i would definitely say that chances on getting people to invest/nor support the project is high.
The thing here is that vloggers is also part of the marketing stuff so budget allocation would be needed and i dont know whats their rates but expect for it to be premium yet 1M subs
do already speaks out.