Potential candidates position themselves for 2016

>> it's time for our weekly roundup of 2016 moves. believe it or not negative ads are already airing in iowa .

>> sometime soon, virginia governmental bob mcdonnell may be in iowa to test the waters for 2016 . don't be fooled. as a candidate, he promised he would never raise taxes, but as governor he pushed the largest tax increase in virginia in history.

>> tea party pay trtriot group is backing that. mcdonnell is the not headed to iowa yet, but several republicans have made it clear this week they're positioning themselves for a presidential run down the road. former florida jeb bush used his book to plant his flag in the field.

>> you're being more open about considering national office than ever before.

>> i'm not saying yes, i'm not saying no.

>> what's different?

>> i've accomplished some things in my life that allow me to have that kind of discretion to be able to think about it.

>> senator rand paul 's filibuster stole the show, however, winning praise from an odd coalition of conservatives, many of whom don't even support what he's trying to do.

>> a man who is, i believe, going to be the logical choice for president of the united states --

>> this is a terrific performance of leadership, of courage, of stamina, determination.

>> the e-mails came flying in. twitter was going nuts.

>> this was to me a seminal event last night that could change the direction that we are all heading.

>> paul agreed in an interview with politico this is an important moment for him.

>> how seriously are you looking at 2016 ?

>> we're looking at it very seriously. i think our party needs something new, fresh, and different.

>> democrats were also making moves this week as well as vice president biden who was pitching himself to a different constituency nearly every day, it seemed, marching it selma on sunday, speaking to aipac on monday, declaring victory on the violence against women 's act, a bill he originally authored when he was in the senate, with women behind him on thursday. meanwhile, maryland governor martin o'malley will give a keynote speech this morning in south carolina . unfortunately for o'malley, just 7% of democrats in his own state put him at the top of their 2016 list compared to the whopping 16% that choose hillary clinton . clinton showed in a quinnipiac poll this week why she can clear the field. governor chris christie is the only governor -- tops paul ryan 50 to 38 and leads marco rubio 50-34. nbc's senior editor mark murray is here. he's the guy that has the coalition already built there that he can inherit from his father. a lot of folks, and you and i have had this conversation before, rand paul had a lot of energy behind him. rand paul seems to be a much better face, much better spoken and has a ton of energy about him.

>> you end up looking at rand paul , he did create a splash this week with what he did on that filibuster, luke. and it was amazing to me, not only the splash that he got among conservative pundits, the rush limbaughs, but also the backlash he got from john mccain and lindsey graham , who said this isn't the type of position on national security our party should be taking.

>> on the democratic side, we saw joe biden 's schedule. seems to touch on all the groups you would need to touch on to come through a democratic primary . but this far out, we're in march of 2013 , it seems to me that it's hillary, and that decision, and that's it. from the aides i've talked to, if she wants it, it's hers. no one can challenge her at this point. there's no barack obama coming around.

>> that's why we'll probably not get an answer from her for a couple of years, which is why all the activity that we're seeing is happening on the republican side . not only was rand paul making waves , jeb bush . we saw marco rubio taking center stage giving his state of the union response to president obama . all these republicans seem to be doing little different things to at least dip their toes in the 2016 waters to prepare themself for something still three years away.

>> the pressure on hillary is unbelievable. lastly, carl levin retiring. this adds the senate's retirement hearten, mike johanns johanns. he's not terribly popular right now. not good news for democrats in this seat.

>> they have to play defense. republicans haven't done well in presidential contests or senate contests in quite a while a while in michigan, but a retirement does create an open seat . some of the names on the democrat side, democrats seem to like congressman gary peters , and then on the republican side one name that's popped up is congressman mike rogers .

>> as well as dave camp . he only has two more years as chairman of the ways and means committee . still