For the Fall 2004 elections, voters will select 34 Senators (currently held by 19 Democrats and 15 Republicans); one-third of the 100 Senate seats are up for election every two years.

The following chart analyzes the potential that a seat might change parties in this election cycle; it is based on analysis from several election consultants. The Senate race is under a microscope this year because the current make-up is xx Republicans, xx Democrats and one Independent; in case of a tie, the Vice President casts the deciding ballot.

The legend for this chart follows:

• Likely: These races have the potential to become competitive.
• Lean: Although a competitive race, one party has an advantage.
• Toss-Up: These are the most competitive races and are too close to call at this time.

See House Races.

Senate Seats That Might Change Party
State	Party	Senator	Status
AR	R	Murkowski	Toss Up
CA	D	Boxer	Likely Democrat Faces B. Jones (R)
CO	R	Campbell	Retiring - Toss Up
FL	D	Graham - Retiring	Toss Up
GA	D	Miller - retiring	Likely Republican Democratic run-off on August 10: Denise Majette and Cliff Oxford
Il	R	Fitzgerald - retiring	Likely Democrat Barack Obama (D) vs. ? (R)
KY	R	Bunning	Likely Republican Faces D. Mongiardo (D)
LA	D	Breaux - Retiring	Toss Up Chris John
MO	R	Bond	Likely Republican
NC	D	Edwards - VP Candidate	Toss Up
OK	R	Nickles - Retiring	Toss Up
PA	R	Specter	Likely Republican
SC	D	Hollings Retiring	Toss Up Inez Tenenbaum (D) vs. Jim DeMint (R)
SD	D	Daschle	Toss Up
WA	D	Murray	Leans Democrat Faces Nethercutt (R)
WI	D	Feingold	Likely Democrat

Senate Seats Unlikely To Change Party
State	Party	Senator
AL	R	Shelby
AR	D	Lincoln
AZ	R	McCain
CT	D	Dodd
HI	D	Inouye
IA	R	Grassley
ID	R	Crappo Unopposed
IN	D	Bayh
KS	R	Brownback
MN	D	Mikulski
ND	D	Dorgan
NH	R	Gregg
NV	D	Reid
NY	D	Schumer
OH	R	Voinovich
OR	D	Wyden
UT	R	Bennett
VT	D	Leahy