The Democrats up include five members who will be 77 years of age or older, five who represent states that went for Sen. John McCain (R-Ariz.) last year and 10 completing their first full term in the chamber.
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“In 2012, their goal is to get Democrats back under 60,” said Jennifer Duffy of The Cook Political Report. “With 24 seats, the mathematical odds are pretty good.”
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About the only feasible GOP targets available are Sens. Jon Kyl (R-Ariz.) and John Ensign (R-Nev.) and possibly the seat left by Sen. Kay Bailey Hutchison (R-Texas), who is likely running for governor.
The map is left that way because of a disastrous 2006 cycle in which the Iraq war, GOP scandals and other factors conspired to send six GOP incumbents to defeat. Democrats took at least seven seats in 2008, but the field of opportunities was much larger.
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The crop includes freshman Sens. Jim Webb (D-Va.), Claire McCaskill (D-Mo.), Sherrod Brown (D-Ohio), Bob Casey Jr. (D-Pa.), Jon Tester (D-Mont.) and Amy Klobuchar (D-Minn.)
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Democrats also might have to deal with open seats left by Sens. Robert Byrd (W.Va.), who would be 95; Daniel Akaka (Hawaii), who would be 88; Edward Kennedy (Mass.), who would be 80; Dianne Feinstein (Calif.), who would be 79; and Herb Kohl (Wis.), who would be 77.
http://thehill.com/campaign-2008/preventing-60-hope-for-republicans-may-be-two-elections-away-2009-04-01.html