The Democrats spent almost $12 million yesterday on ad buys. After adding that sum to money already spent by both parties (and their surrogates), these are the top races ordered by total money spent to date:
There are three seats that may be considered "lost" already, TX-22 - DeLay, FL-16 Foley and AZ-08 Tancretin, leaving the Democrats looking for twelve seats. The Democrats spent 80% of their money on the races shown bold. The Soros/Emily's Lister's will pick up the slack in NM-01, OH-15 and VA-02.
Right now I rate, CT-05, OH-18, KY-04, VA-02, OH-15 and AZ-05 as Republican holds, leaving sixteen seats from this list in contention (in my world). My reasoning involves incumbency, turnout and plurality margins that I would be happy to explain if anyone in the entire world cared.
All the Democrats have to do is bat .750 for the rest of the season and they clinch the title.
32 minutes ago