Sen. Carl Levin, D-Mich., won't run in '14

WASHINGTON, March 7 (UPI) -- Sen. Carl Levin, D-Mich., the longest-serving U.S. senator in Michigan history, announced Thursday he will not seek a seventh term next year.

President Obama responded to Levin's announcement with accolades for the 78-year-old lawmaker.

"If you've ever worn the uniform, worked a shift on an assembly line or sacrificed to make ends meet, then you've had a voice and a vote in Sen. Carl Levin," Obama said in a statement released by the White House. "No one has worked harder to bring manufacturing jobs back to our shores, close unfair tax loopholes, and ensure that everyone plays by the same set of rules.

"As chairman of the Armed Services Committee, Senator Levin is a true champion for all those who serve, and his tireless work will be missed not just in his home state of Michigan, but by military families across our country."

Levin called his decision to leave the Senate in less than two years an "extremely difficult" decision but said he and his wife Barbara decided he can best serve Michigan and the nation "by doing my job without the distraction of campaigning for re-election."

Among other issues, Levin said he would concentrate on closing corporate tax loopholes that are a "drain on our treasury."

"The huge loss of corporate tax receipts caused by the shift of U.S. corporate tax revenue to offshore tax havens is but one example of the egregious tax loopholes that we must end," he said in a statement posted on his official website. "Thirty of our most profitable companies paid no taxes over a recent three-year period although they had over $150 billion in profits.

"Tax avoidance schemes that have no economic justification or purpose other than to avoid paying taxes may be legal but they should not be.

"These schemes add hundreds of billions of dollars to the deficit. They lead to cuts in education, research, national security, law enforcement, infrastructure, food safety and other important investments in our nation. And they add to the tax burden of ordinary Americans who have to pick up the slack and accelerate the economic inequality in our country."

Levin said he will work to further the comeback of the U.S. manufacturing sector, deal with military readiness and veterans' issues, and end what he called "a growing blight" on the U.S. political system, "the use of secret money to fund political campaigns."