I've found a keyphrase (4 words) that seems advertiser competitive with the top and sidebar positions on Google's results page full. They're paying up $11 for the top listing, and the niche is competitive at the publisher level.

I want to get the number one position without spending a small fortune in SEO, but it's going to be a very hard task, so I need some advice.

I won't make the niche public or my URL, but I can tell you that none of listing URLs are a match, all listings are a single listing, and page one for the phrase looks like this;

1. PR7 exact match in title, phrase in content
2. PR6 exact match in title, meta description and keywords, similar phrase in content
3. PR6 exact match in title and description, similar match in content
4. PR4 affiliate site, close match in title, similar match in content
5. PR6 keywords in title and description but not an exact match, keywords used in content
6. PR5 keywords in title and description but not an exact match, keywords used in content
7. PR5 keywords in title and description but not an exact match, keywords used in content
8. PR3 exact match in title and keywords, close match in description, exact match in content
9. PR5 close match in description, keywords appear in content
10. PR3 similar match in title and descriotion, keywords used in content

I have a general blog, PR6 which ranks on either page one or page two for another long tail within the same niche as the one I want to target.

What would I need to do to rank on page one of the niche against those other sites, and what might be involved in getting number one?