The bottom line is that no Democratic seat looks to be in serious danger, although four are probably in play. On the other hand, a full five Republican seats are not only in danger of switching to the Democrats, but likely would if the elections were held today. Another four Republican seats are potentially in play.
| Rank | State | Seat | Approval Rating | Candidates | Rasmussen Poll | Money Race (COH) |
| 1 | Pennsylvania | Rick Santorum | 43 - 50 | Republican Rick Santorum Democrat Bob Casey | Casey 50 Santorum 39 (7/26) | Santorum $8.8 million Casey $4.5 million |
| 2 | Montana | Conrad Burns | 37 - 57 | Republican Conrad Burns Democrat Jon Tester | Tester 50 Burns 43 (7/6) | Burns $2.2 million Tester $0.5 million |
| 3 | Rhode Island | Lincoln Chafee | 48 - 46 | Republican Lincoln Chafee or Steve Laffey Democrat Sheldon Whitehouse | Whitehouse 46 Chafee 41 (7/11) | Whitehouse $1.8 million Chafee $1.3 million |
| 4 | Ohio | Mike DeWine | 45 - 45 | Republican Mike DeWine Democrat Sherrod Brown | Brown 44 DeWine 42 (7/27) | DeWine $6.6 million Brown $3.7 million |
| 5 | Missouri | Jim Talent | 49 - 44 | Republican Jim Talent Democrat Claire McCaskill | McCaskill 45 Talent 42 (7/20) | Talent $6.9 million McCaskill $2.8 million |
| 6 | Tennessee | Bill Frist | Retiring | Republican Bob Corker or Van Hilleary or Ed Bryant Democrat Harold Ford | Corker 49 Ford 37 (7/16) | Ford $1.8 million Corker $1.2 million |
| 7 | Nevada | John Ensign | 52 - 38 | Republican John Ensign Democrat Jack Carter | Ensign 46 Carter 39 (7/31) | Ensign $3.3 million Carter $0.4 million |
| 8 | Virginia | George Allen | 51 - 39 | Republican George Allen Democrat James Webb | Allen 50 Webb 39 (7/18) | Allen $6.6 million Webb $0.4 million |
| 9 | Arizona | Jon Kyl | 47 - 40 | Republican Jon Kyl Democrat Jim Pederson | Kyl 53 Pederson 34 (7/18) | Kyl $7.1 million Pederson $1.7 million |
| 10 | Utah | Orrin Hatch | 58 - 37 | Republican Orrin Hatch Democrat Pete Ashdown | No Poll Available | Hatch $2.5 million Ashdown $13,000 |
| 11 | Wyoming | Craig Thomas | 62 - 29 | Republican Craig Thomas Democrat Dale Groutage | Thomas 59 Groutage 32 (7/6) | Thomas $1.1 million Groutage $8,000 |
| 12 | Texas | Kay Bailey Hutchinson | 60 - 31 | Republican Kay Bailey Hutchinson Democrat Barbara Ann Radnofsky | Hutchinson 58 Radnofsky 31 (7/13) | Hutchinson $9.2 million Radnofsky $0.3 million |
| 13 | Maine | Olympia Snowe | 72 - 24 | Republican Olympia Snowe Democrat Jean Hay Bright | Snowe 69 Bright 22 (7/19) | Snowe $1.2 million Bright $100 |
| 14 | Mississippi | Trent Lott | 68 - 28 | Republican Trent Lott Democrat Erik Fleming | Lott 66 Fleming 29 (2/13) | Lott $2.0 million Fleming $600 |
| 15 | Indiana | Dick Lugar | 65 - 29 | Republican Dick Lugar | No Opposition | Lugar $4.0 million |
| Rank | State | Seat | Approval Rating | Candidates | Rasmussen Poll | Money Race (COH) |
| 1 | Maryland | Paul Sarbanes | Retiring | Democrat Ben Cardin or Kweisi Mfume Republican Michael Steele | Cardin 47 Steele 41 (7/10) | Steele $3.0 million Cardin $2.3 million |
| 2 | New Jersey | Bob Menendez | 45 - 39 | Democrat Bob Menendez Republican Tom Kean | Menendez 44 Kean 38 (7/25) | Menendez $7.4 million Kean $2.8 million |
| 3 | Minnesota | Mark Dayton | Retiring | Democrat Amy Klobuchar Republican Mark Kennedy | Klobuchar 50 Kennedy 38 (8/1) | Kennedy $4.1 million Klobuchar $3.5 million |
| 4 | Washington | Maria Cantwell | 49 - 43 | Democrat Maria Cantwell Republican Mike McGavick | Cantwell 48 McGavick 37 (8/1) | Cantwell $6.4 million McGavick $1.1 million |
| 5 | Michigan | Debbie Stabenow | 50 - 39 | Democrat Debbie Stabenow Republican Michael Bouchard or Keith Butler | Stabenow 54 Bouchard 34 (4/26) | Stabenow $4.4 million Bouchard $0.5 million |
| 6 | Nebraska | Ben Nelson | 68 - 27 | Democrat Ben Nelson Republican Pete Ricketts | Nelson 57 Ricketts 31 (7/11) | Nelson $2.1 million Ricketts $1.1 million |
| 7 | West Virginia | Robert Byrd | 64 - 33 | Democrat Robert Byrd Republican John Raese | Byrd 57 Raese 34 (4/25) | Byrd $2.6 million Raese $0.2 million |
| 8 | Florida | Bill Nelson | 48 - 33 | Democrat Bill Nelson Republican Katherine Harris | Nelson 61 Harris 33 (7/25) | Nelson $12.1 million Harris $2.6 million |
| 9 | North Dakota | Kent Conrad | 72 - 23 | Democrat Kent Conrad Republican Dwight Grotberg | Conrad 57 Grotberg 35 (1/25) | Conrad $3.5 million Grotberg $19,000 |
| 10 | Connecticut | Joe Lieberman | 54 - 41 | Democrat Joe Lieberman or Ned Lamont Republican Alan Schlesinger | Lamont/Lieberman 40 Schlesinger 13 (7/20) | Lieberman $3.5 million Lamont $0.4 million Schlesinger $76,000 |
| 11 | New Mexico | Jeff Bingaman | 58 - 33 | Democrat Jeff Bingaman Republican Allen McCulloch | Bingaman 59 McCulloch 33 (6/27) | Bingaman $1.8 million McCulloch $2,000 |
| 12 | Vermont | Jim Jeffords | Retiring | Independent Bernie Sanders Republican Richard Tarrant | Sanders 67 Tarrant 29 (5/9) | Sanders $2.0 million Tarrant $0.8 million |
| 13 | Wisconsin | Herb Kohl | 57 - 33 | Democrat Herb Kohl Republican Robert Lorge | Kohl 60 Lorge 27 (7/12) | Kohl $2.0 million Lorge $1,000 |
| 14 | California | Dianne Feinstein | 57 - 34 | Democrat Dianne Feinstein Republican Dick Mountjoy | Feinstein 60 Mountjoy 33 (7/5) | Feinstein $8.0 million Mountjoy $21,000 |
| 15 | Delaware | Tom Carper | 62 - 31 | Democrat Tom Carper Republican Jan Ting or Mike Protack | No Polling Available | Carper $2.5 million Ting $78,000 |
| 16 | New York | Hillary Clinton | 62 - 36 | Democrat Hillary Clinton Republican John Spencer or KT McFarland | Clinton 61 Spencer 31 (7/31) | Clinton $22.0 million Spencer $0.6 million |
| 17 | Massachusetts | Ted Kennedy | 59 - 37 | Democrat Ted Kennedy Republican Kenneth Chase | No Polling Available | Kennedy $8.7 million Chase $35,000 |
| 18 | Hawaii | Daniel Akaka | 51 - 43 | Democrat Daniel Akaka or Ed Case Republican Mark Beatty | No Polling Available | Akaka $1.0 million Beatty (No Report) |
