Finding opinionated blog posts is still an open problem in information retrieval, as exemplified by the recent TREC blog tracks. Most of the current solutions involve the use of external resources and manual efforts in identifying subjective features. In this paper, we propose a novel and effective dictionary-based statistical approach, which automatically derives evidence for subjectivity from the blog collection itself, without requiring any manual effort. Our experiments show that the proposed approach is capable of achieving remarkable and statistically significant improvements over robust baselines, including the best TREC baseline run. In addition, with relatively little computational costs, our proposed approach provides an effective performance in retrieving opinionated blog posts, which is as good as a computationally expensive approach using Natural Language Processing techniques. Categories and Subject Descriptors: H.3.3 [Information Storage and Retrieval]: Information Sear...