Dem. Senator Harkin won’t seek re-election

>>> developing now democratic senator tom harken of iowa said he's stepping down. he will not seek re-election next year. he was instrumental in urging senators to back the 2010 health care bill. on the phone nbc news capitol hill correspondent kelly o'donnell. why does he not want to continue in the senate?

>> it's always interesting, t.j., to take a look at the motivations behind these big moves because they have huge implications. tom harken said there are two reasons. at the end of this term he will have served the people of iowa for 40 years. he believes it's time to let someone else step in he thinks that's good for his state. he also talks about making a promise to his wife ruth that they would be able to live together and do the kind of things they have wanted to do. as you remember, people who are in congress often live apart from their spouse for at least part of year. and many of them, especially those who have served for a long time when we have conversations in the hallways do talk about the very simple desire to spend more time with their family. that's often a buzz phrase in washington that people think is being used to step aside . in tom harkin 's case it seems to be a simple equation of he feels it's time. why? because as a democrat he is in the majority. he is a powerful chairman of a committee. he has about $3 million in his campaign war chest . so he has the tools. what it does do right now is put into play a state that has as its other senator a republican, chuck grassley . there are republicans in their house representation. and it's a state that has supported president obama . it's one of those states that's highly sought after. in talking with people from the committee that runs these campaigns for senate democrats , what they are grateful about is the early notice. because tom harkin is giving them a little less than two years to make this happen they think they can field a candidate. we've seen others, jay rockefeller of west virginia has also made the decision he will not run. just friday we heard from a republican of georgia, saxby chambliss , who was the biggest surprise that he is not going to seek re-election. in this case he did cite the gridlock in washington, the frustration about not being able to get enough done. those are three formidable names in the u.s. senate who will not be there after 2014 . so it will change the makeup of things. it makes the senate races, there will be 35 seats in 2014 . it begins to already feel campaign energy going.

>> you certainly understand it better than most covering capitol hill . but the power he wields and the influence. you talked about implications. just how much will he be missed, that influence and just understanding the senate? he talked about some of the committees he's on and influence those real world implications.

>> seniority is one of the great currencies in the u.s. senate . we have seen a lot of seniority begin to dissipate. went you have somebody with 40 years in congress like tom harkin that's a lot of concentrated power. he said he wants to work on issues that are very important to progressive democrats . the enforcement and full implementation of the president's health care law . doing more to protect workers' pensions which is always an issue as the economy is in struggle. and he works as an appropriate rater those who help decide where the funds are going. he's promising his state he'll work very hard on that. so he is at a point in his mid 70s where he's not going to work as hard. he says he won't leave public life but he's going to make this shift. when we see these power changes it really does have implications to the kinds of bill that is get passed or don't get passed to the sort of centers of gravity in congress. so for people who enjoy politics, this is a very interesting development.

>> kelly o'donnell with the breakdown for us. thank you so much.