Yes and no. First of all, it must be an authorized reseller (I believe both Amazon and Newegg apply). However, historically Dell's warranty is applicable to the person/entity that bought their hardware...in other words, Dell services the warranty (or replacement) to Newegg, then Newegg takes care of you.
But it's a PITA to get the "paperwork" done, expect long hold times, then expect a long wait for service or satisfaction.
YMMV on above description. But if you're looking to save 10 bucks, and above description happens to you, it's probably not worth it if there was a $20 difference.