NEW YORK, NY December 15, 2007 —Illinois Senator Barack Obama is pushing back against the Clinton campaign's argument that he hasn't been "vetted" sufficiently to be the Democratic nominee for president. WNYC's Andrea Bernstein is with the Obama campaign in Iowa and has this report.

REPORTER: During a television interview Friday, Hillary Clinton said her candidacy would have "no surprises," though she insisted afterwards she wasn’t referring to anyone other than herself. But in Oelwein Iowa Friday night, Obama argued that's the wrong argument for Democrats.

OBAMA: Poll testing because we're worried about what Mitt or Rudy, who are those other guys, it just won't do, if we want to really make a change then we can't live in fear of losing.

REPORTER: Obama said instead it's time to be part of a generation that stands up. After a long period of maintaining a slight lead in the polls, Clinton has slipped in Iowa. There are less than three weeks to the caucuses and all the Democratic candidates are planning intense weeks of stumping in Iowa.

Reporting from Oelwein Iowa, For WNYC, I'm Andrea Bernstein.