Sen. Kent Conrad, D-N.D., said he will retire from Congress and won't run for re-election next year.

Conrad, chairman of the Senate Budget Committee, said in a statement that he wants to focus on reducing the nation's $14 trillion debt and on energy issues.

He said it is important to "spend my time and energy trying to solve these problems than to be distracted by a campaign for re-election."

Conrad, 62, has been in the Senate since 1987 and is a member of President Obama's debt commission. Conrad's retirement creates a pickup opportunity for Republicans, who easily won North Dakota's other Senate seat and its lone House seat in the 2010 elections.

Obama said Conrad has "been a good friend to me" and a "tireless advocate" for North Dakotans. "He has shown an unmatched dedication to putting our country on a sound fiscal path and a commitment to meeting our nation's energy challenges," Obama said in a statement.

In his statement, Conrad praised his friends Byron Dorgan, who retired from the Senate earlier this month,and Earl Pomeroy, the North Dakota congressman who was defeated in November.

"We worked hard to produce results for our state and our country. It is an experience I will never forget," Conrad said.

The 2012 Senate elections could be pivotal for Democrats, who now have a 53-47 voting edge. Next year, Democrats will have to defend 23 Senate seats -- including those of two independents who vote with them. Republicans have 10 seats up for re-election.

Sen. Patty Murray, D-Wash., chairwoman of the Democratic Senatorial Campaign Committee, praised Conrad as a "stalwart fighter."

She said there are "a number of potential Democratic candidates who could make this race competitive." Murray said she expects a "contentious primary battle" among Republicans.

"North Dakotans have a long history of electing moderate Democrats to the Senate, and we believe they will have an opportunity to keep up the tradition next November," Murray said.

Brian Walsh of the National Republican Senatorial Committee sent an e-mail to reporters with a snippet of a Washington Post report on Conrad's retirement, reminding them that Republican John Hoeven won Dorgan's Senate seat with 76.2% of the vote.

"Sen. Conrad's retirement dramatically reshapes this race in the Republicans' favor," Walsh said. "We believe this race represents one of the strongest pickup opportunities for Senate Republicans this cycle and will invest whatever resources are necessary to win next year."