Using Someone Else's Web Content

I am looking to develop a website that aggregates and summarizes the blog content of other bloggers in the US in X amount words in 1 place on my website. I will be paraphrasing the original content in my own words and will be providing credits and hyperlink back to the original blog content. My question is that can I run into any potential copyright issues. Is such usage covered under the fair use policy? Do I still necessarily need to take permission from the blog content owner for such usage.