Maine Senator Olympia Snowe is not running for reelection, according to Twitter:

Maine Republican Sen. Olympia Snowe is not running for re-election, according to 2 source familiar with decision. HUGE news.
— The Fix (@TheFix) February 28, 2012

Find a little more here. Snowe was one of the last moderate Republicans, and all that she got for her trouble was grief from teabaggers. According to Sam Stein on Twitter, Snowe says "I do find it frustrating...that an atmosphere of polarization and 'my way or the highway' ideologies has become pervasive" in American politics. This should be good news for Senate Democrats in November.

UPDATE: Snowe's whole statement is after the jump.

After an extraordinary amount of reflection and consideration, I am announcing today that I will not be a candidate for re-election to the United States Senate.

After 33 years in the Congress this was not an easy decision. My husband and I are in good health. We have laid an exceptionally strong foundation for the campaign, and I have no doubt I would have won re-election. It has been an indescribable honor and immeasurable privilege to serve the people of Maine, first in both houses of Maine’s legislature and later in both houses of Congress. To this day, I remain deeply passionate about public service, and I cherish the opportunity I have been given for nearly four decades to help improve the lives of my fellow Mainers.

As I have long said, what motivates me is producing results for those who have entrusted me to be their voice and their champion, and I am filled with that same sense of responsibility today as I was on my first day in the Maine House of Representatives. I do find it frustrating, however, that an atmosphere of polarization and ‘my way or the highway’ ideologies has become pervasive in campaigns and in our governing institutions.

With my Spartan ancestry I am a fighter at heart; and I am well prepared for the electoral battle, so that is not the issue. However, what I have had to consider is how productive an additional term would be. Unfortunately, I do not realistically expect the partisanship of recent years in the Senate to change over the short term. So at this stage of my tenure in public service, I have concluded that I am not prepared to commit myself to an additional six years in the Senate, which is what a fourth term would entail.

As I enter a new chapter, I see a vital need for the political center in order for our democracy to flourish and to find solutions that unite rather than divide us. It is time for change in the way we govern, and I believe there are unique opportunities to build support for that change from outside the United States Senate. I intend to help give voice to my fellow citizens who believe, as I do, that we must return to an era of civility in government driven by a common purpose to fulfill the promise that is unique to America.

In the meantime, as I complete my third term, I look forward to continuing to fight for the people of Maine and the future of our nation. And I will be forever and unyieldingly grateful for the trust that the people of Maine have placed in me, and for the phenomenal friendship and assistance I have received over the years from my colleagues, my supporters, and my staff, both in Maine and in Washington.