Democratic Senator Herb Kohl from Wisconsin, who is completing his fourth term, announced today that he will not seek re-election. This is a devastating loss for the Democrats, and makes it much less likely that they will retain control of the Senate in next year’s elections.

478px Herbert Kohl  official photo

Kohl is independently wealthy and has self-funded his previous campaigns. He owns the Milwaukee Bucks, presumably still an NBA team.

Kohl’s departure makes him the sixth Democrat to leave. He joins Akaka (HI), Bingaman (NM), Conrad (ND), Lieberman (CT), and Webb (VA) who had all previously announced that they would not attempt to run for another term. What makes this loss particularly difficult for the Democrats is that Wisconsin has moved away from their party in last year’s elections. Russ Feingold lost his Senate seat to Ron Johnson. As well, the governor’s office was taken by the Republicans. So, there is a high likelihood, now that they have lost the incumbency advantage, that they will also lose Kohl’s seat as well.

Kohl will be little remembered in the Senate. He rarely did or said anything notable during his four terms. His main value was that he voted the way the party ‘encouraged’ him to vote, so his support was never in question. But the policy effects of his tenure are negligible.

The Democrats are set to defend 23 seats next November, while the Republicans only must try to protect 10. Since the Democrats have a three seat advantage (four, if Obama retains the presidency), the likelihood is that the Republicans will become the majority party.

Who are some likely candidates to run for Kohl’s seat? Well, Feingold is probably the most well-known Democrat and would have an advantage over any primary opponent. Since the election, he has become involved with Progressives United, a liberal political action committee. The Republicans may attempt to get Paul Ryan, the Chair of the House Budget Committee, to run for the seat. Ryan will likely be targeted by the Democrats next year since his district is very competitive. Another potential candidate is Scott Walker, the Governor, especially if the recall votes on Republican state senators this summer work out poorly for him.

The head of the Democratic Senatorial Campaign Committee is Patty Murray (D-WA). Her intellectual alacrity has been in doubt since she was first elected to the body. Now that the odds are reducing that the party will maintain control, it is unlikely that she will be able to find replacement candidates who are of high enough quality to retain the seats.