This is from the latest Zogby interactive poll, published by the Wall Street Journal, released late last month.
Democratic Incumbents:
New York: Clinton 58%, Pirro 38%
New Mexico: Bingaman: 52%, Wilson 39%
Michigan: Stabenow 53%, Butler 38%
Florida: Nelson 49%, Harris 40% (other polls give Nelson a bigger lead).
Wisconsin: Kohl: 49%, Thompson 46% (Tommy Thompson, I'm almost sure will not run).
Washington: Cantwell: 50%, McGarick: 41%
Republican Incumbents:
Texas: Hutchinson: 55%, Kirk: 38%
Virginia: Allen: 49%, Beyer: 42%
Missouri: Talent: 46%, McCaskill: 46%
Pennsylvania: Casey: 50%, Santorum: 40% (a new Rasmussen poll out today gives Casey a 20-point lead)
Ohio: Hacket: 45%, Dewine: 35%
Nevada: Ensign: 45%, Goodman: 42%
Arizona: Kyl: 52%, Pederson: 42%
Open Seats:
Minnesota: Klobuchar (D): 49%, Kennedy (R): 43%
Maryland: Cardin (D): 50%, Steele (R): 42%
Tennessee: Ford (D): 41%, Bryant (R): 48%
New Jersey: Andrews (D): 37%, Kean (R): 41% (but if Gov-elect Corzine appoints Acting Gov. Cordey to the Senate we have an excellent shot of winning, since Cordey has a 71% approval rating).
Not included in the polls are Rhode Island, where Dems have a shot at beating Chafee and Vermont where Independent Bernie Sanders will probably win and vote with the Democrats.
There is a chance too that Trent Lott will not run again in Mississippi and if Democrat Gene Taylor runs he might have a chance to win this seat.
Summary:
Dems have good shots to pick up these GOP seats:
Ohio
Pennsylvania
Rhode Island
Missouri
Tennessee
Nevada
Virginia (Allen's 7-point lead is not impressive)
and possibly Arizona, Kyl's 10-point lead is not overwhelming.
The Republicans have a shot in:
Wisconsin (if Thompson runs)
New Jersey (if Cordey is not the Democratic candidate)
Washington (Cantwell, I think is vulnerable, despite her 9-point lead)
Maryland--an open seat and depends on who the Dems nominate.
Minnesota--another open seat, but I think the Dems ultimately will win this one.
If it's a strong Democratic year like '05 we could see coast to coast victories with Democrats who seem in peril winning and incumbent republicans who are running even or a few points ahead losing. In that case I think it is very possible for the Dems to get the six seats necessary to win back control of the Senate.
My guess right now is that Democrats will win between 4-7 Senate seats in 2006.
http://online.wsj.com/public/resources/documents/info-flash05a.html?project=elections06