Senator Byron Dorgan (D-ND) announced today that he not seek reelection in 2010 and will retire from the Senate at the end of this year.

Dorgan has represented his state for 30 years, first in the House and then in the Senate.

The Wall Street Journal, notes that Dorgan is "the first Democratic senator to decide not to seek
re-election in what looks to be shaping up as a touch election cycle
for the party….[and would] likely face a difficult re-election fight given
that North Dakota is one of the reddest states in the country."

According to the Huffington Post, Dorgan said he:

"[R]eached the decision after
discussing his future with family over the holidays. Dorgan, 67, said
he "began to wrestle with the question of whether making a commitment
to serve in the Senate seven more years was the right thing to do."

"Although
I still have a passion for public service and enjoy my work in the
Senate, I have other interests and I have other things I would like to
pursue outside of public life," he said in a statement."

Whatever the reasoning behind his decision, Dorgan’s retirement is widely seen as a blow to the Democrats.  Ken Johnson of HuffPo writes:

Dorgan’s decision stunned members of his party, who control the Senate
but are facing spirited challenges from Republicans in several states.
Democrats were confident heading into the new year that Dorgan would
run for re-election even as rumors intensified that Republican Gov.
John Hoeven would challenge him in November.

Hoeven has not announced a candidacy but national Republicans expect
he will. 

Both pro-choice and anti-choice groups rate Dorgan as a Senator with a
"mixed record" on reproductive rights issues. Nonetheless, given his state, Dorgan’s voting record is pretty progressive on at least some issues otherwise driven completely by ideology. 

According to OntheIssues.org, for example, in 2005 Dorgan voted in favor of allocating $100 million to reduce unintended pregnancy among teens through comprehensive sex education and access to contraceptive supplies.  In 2000, he voted against maintaining the ban on providing abortions to women in the military who chose to end an unintended pregnancy.  In 2007, he voted against banning grants from the Department of Health and Human Services (HHS) to organizations that perform abortions.  He has voted against withholding money from the United Nations Population Fund (UNFPA) and for expanding stem cell research.  While he does not have a perfect pro-choice record–he voted for the so-called "partial birth" abortion ban, for example–he certainly voted in favor of public health, medical evidence, and human rights on many occasions.  

The Journal states that:

Sen. Dorgan had long fought to lift a ban on Americans seeking to
import pharmaceutical drugs from other countries to help alleviate the
high price of drugs in the U.S.

After several attempts by Sen. Dorgan to seek a vote on the matter,
one was eventually held as part of the health care debate in the Senate
last year.

But it was watered down in order to retain the support of other Democratic lawmakers for the wider health care effort.

Johnson writes:

Democrats insist they will field a strong candidate to run in
Dorgan’s place, and recruitment already was under way Tuesday.
Democratic Rep. Earl Pomeroy, who was first elected to the House in
1992, could be interested in seeking the Senate seat, along with Heidi
Heitkamp, a former state attorney general and tax commissioner who was
defeated by Hoeven in the 2000 gubernatorial race.

Dorgan’s announcement could complicate efforts by Democrats to
maintain their advantage in the Senate, where they hold an effective
60-40 majority, including two independents who align themselves with
Democrats. That’s just enough to break Republican filibusters if all 60
stick together.

Many Democratic incumbents could face challenges in 2010 amid high
unemployment rates, concerns about the wars in Iraq and Afghanistan and
anger at incumbents.