"AD BLITZ UNLEASHED Tue Sep 26 2006 18:25:05 ET The Republican Party has unleashed a long-planned battery of negative ads against Democratic challengers in House and Senate races across the country, employing the fruits of more than a year of research into the backgrounds of Democratic candidates. Just as Democrats have launched an unusually aggressive barrage of negative advertisements intended to tie Republican incumbents to an extremely unpopular Congress, and portray them as captives to big business, pharmaceutical concerns and the oil industry. NEW YORK TIMES reporter Adam Nagourney plans a Page One Splash for Wednesday, declaring: "The result has been what aides to both sides described on Tuesday as the most toxic midterm political environment in memory." Developing...