Dems strategy to retake the Senate: Ralistic or Wishful?

This from Sen. Schumer (NY). Yesterday, leading conservative pundit Robert Novak surveyed the electoral landscape and concluded:
"Rick Santorum remains far behind in Pennsylvania. Conrad Burns is in trouble in Montana. Jim Talent trails in Missouri. Mike DeWine is threatened by a noxious Republican atmosphere in Ohio. Lincoln Chafee is endangered in Democratic Rhode Island. John Kyl faces a surprisingly tough race in Arizona. Despite excellent candidates in Minnesota and Washington State, no Republican challenger for a Democratic-held Senate seat is in the lead. Thus, a six-seat takeover, capturing the Senate, is possible."
And Novak didn't even mention Tennessee, where Harold Ford is making a strong play for Bill Frist's open seat, and Virginia, where Jim Webb is nipping at the heels of George Allen.

Is Sen .Schmer overly optimistic given all these races (save PA) are very close and worst case (save PA) could be lost?
More focus from the Dems on thier message including the Contract 2 previously cited is needed to make the probability of retaking the Senate convincing. We have communicated this view to the Senator.