One cannot just pick and choose the most favorable polls to build a case that these election results were suspiciously out of whack. Look at the various polls for GA, NH, and TX here:
http://www.realclearpolitics.com/Congressional/Senate_02_Polls.html
It then becomes apparent that the results in these races were in line statiscally speaking with any margain of error listed.
MN was a special case obviously. The day before the election debate and the whole Wellstone Memorial debacle swung things dramatically there. The party made a mistake pulling an out of touch Fritz Mondale into the race. Mondale's son, Ted, probably would have won.