WASHINGTON ( CNN ) -- Sen. Barack Obama said Thursday that the most important thing he could achieve as president would be to deal with Iraq and the threat of al Qaeda in Afghanistan while improving `` our influence around the world . '' Sen. Barack Obama , in his first interview since the North Carolina and Indiana primaries , speaks with Wolf Blitzer . In his first interview since the North Carolina and Indiana primaries , Obama said he thinks the United States ' influence around the world has been diminishing . `` The world wants to see the United States lead . They 've been disappointed and disillusioned over the last seven , eight years , '' he told CNN 's Wolf Blitzer in an interview on `` The Situation Room . '' `` I think there is still a sense everywhere I go that if the United States regains its sense of who it is and our values and our ideals , that we will continue to set the tone for a more peaceful and prosperous world . '' Watch the full interview with Obama » . Obama said he thinks the way the war in Iraq has been handled has kept the United States from focusing on key issues like energy policy , global warming and the economy . Americans want to succeed , he said , `` but we 're going to have to make some investments and ensure that the dynamism and the innovation of the American people is released . '' `` It 's very hard for us to do that when we 're spending close to $ 200 billion a year in other countries , rebuilding those countries instead of focusing on making ourselves strong , '' he said . Obama downplayed headlines and stories , such as the cover of Time magazine , that have declared him the Democratic presidential nominee . `` I do n't want to be jinxed . We 've still got some work to do , '' he said . Watch an analysis of some of Obama 's comments » . Obama predicted that he and Sen. Hillary Clinton would probably split the remaining contests and said Clinton would win the upcoming primary in West Virginia by a `` big margin . '' Obama won North Carolina by a 14-point margin Tuesday . Clinton squeaked out a win in Indiana by 2 points . In the days after those contests , some top Democrats have called on Clinton to step aside . Obama deflected a question about a potential joint ticket with the New York senator , saying it 's too early to start thinking about running mates . `` Sen. Clinton has shown herself to be an extraordinary candidate . She 's tireless , she 's smart , she 's capable , and so obviously she 'd be on anybody 's short list to be a potential vice presidential candidate , '' he said . `` But it would be presumptuous of me at this point ... to somehow suggest that she should be my running mate . '' Watch viewer responses to question : Should Obama offer Clinton the No . 2 spot ? » . Terry McAuliffe , a former Democratic National Committee chairman and a co-chairman of Clinton 's campaign , commented Thursday on the possibility of a joint ticket . `` I think what she 's interested in being the nominee of the party . ... We 're fighting hard for it . This woman has been working tirelessly through this campaign . ... Hillary has earned the right to do whatever she wants to do . '' Obama said he 's ready for what would be the next phase if he becomes the nominee : a matchup against Sen. John McCain , the presumptive GOP candidate . Obama said he was offended when McCain said last month , `` It 's very clear who Hamas wants to be the next president . '' `` I think it 's disappointing because John McCain always says , 'Well , I 'm not going to run that kind of politics , ' and then to engage in that kind of smear I think is unfortunate , particularly since my policy on Hamas has been no different than his , '' Obama said . `` And so for him to toss out comments like that , I think , is an example of him losing his bearings as he pursues this nomination . '' When asked to respond to McCain supporters -- such as former Massachusetts Gov . Mitt Romney -- who have said Obama is not ready to be commander in chief , the senator from Illinois said he thinks what people are looking for is `` good judgment . '' `` I think I 've consistently displayed the kind of judgment that the American people are looking for in the next president , '' he said . Watch Obama say why he 's qualified to be president » . Romney responded later on `` The Situation Room , '' saying `` The truth of the matter is just as I said , that he does n't have a record of accomplishments in the private sector or in the governmental sector ... has n't pushed a major piece of legislation . `` He seems like a charming guy who 's very well-spoken . But in terms of actually having led , actually having accomplished something , actually having a kind of leadership that America needs at a critical time with our economy ... he 's untested . ... Frankly , Sen. McCain is someone who is tested and very proven , '' he added .
Obama says he thinks U.S. influence has been diminishing . Candidate downplays notion that he is already the Democratic nominee . Obama says it 's too early to discuss potential running mates . Clinton camp says she 's `` fighting hard '' to be nominee , not running mate .