All-out fight for GOP nomination, White House

>>> tonight, president obama is wrapping up day three of a ten-day vacation trip to martha's vineyard with his family. and while the white house calls this a working vacation, the president's republican rivals are working the campaign trail targeting the president and the economy. nbc's mike viqueira has our report.

>> reporter: rick perry was back on the campaign trail today in south carolina , just seven days after joining the race, the conservative texan is now considered a top-tier candidate.

>> getting america working again is the focus -- it's like a laser on our campaign.

>> $16 trillion --

>> reporter: perry's rise has come in part at the expense of another frontrunner, michele bachmann , who won the iowa straw poll just a week ago. both perry and bachmann are competing for some of the same conservative tea party voters. but experts say that race to the right might end up helping president obama with key independent voters next year.

>> to the extent the republicans playing up their differences and their positions, some of which are pretty conservative, that's good for the president.

>> reporter: but the economy remains bad. three days into his august break on martha's vineyard, mr. obama used his weekly address to pledge more action and to slam congress.

>> we need them to put aside their differences to get things done.

>> reporter: since world war ii , no president has been reelected with an unemployment rate of over 575%. that rate now stands at 9.1%. and experts predict it will be around that on election day 2012 .

>> at a minimum, it's going to feel recessionary and may be in a recession.

>> reporter: are the weak economic a big target, republicans have not let up in their attacks on the president.

>> the fact that this recession went on so long and has been so difficult from which to recover, a lot of the blame for that lies at the feet of the lack of presidential leadership.

>> reporter: with campaign season now in full swing, republicans are in an all-out fight to take on a president who could be politically weakened by struggling economy. mike viqueira, nbc news, washington.