Barack Obama A day after over nine-thousand Democrats gathered in Des Moines to hear from six presidential candidates competing for support in Iowa’s Caucuses, Hillary Clinton’s two primary competitors kept questioning whether she can win in November of next year.

Barack Obama went NBC’s "Meet the Press" on Sunday morning and while Obama told host Tim Russert he believed Hillary Clinton could win the 2008 general election, Obama quickly offered a caveat. believe that it’s going to be harder for her to win because I think a lot of voters go in with some preconceptions about her that are going to be very difficult to overcome."

Obama said it will be hard for Clinton, if she is elected, to build "a new working majority" that would be able to enact change on a number of fronts. "I want to provide health insurance to every single American. We can’t do that with a 50-plus-one majority. I want to get serious about climate change. We can’t do that with a 50-plus-one majority," Obama said. "I believe I’ve got a better chance (than) another other Democratic candidates to transform the political landscape in a way that hasn’t been done in the past."

Obama vowed to continue to highlight what he sees as inconsistencies in Clinton’s record. "Look, we’re running for the presidency of the United States of America not student council president," Obama said. "That means that the American people have a right to know what exactly we intend to do as president and if I believe that one of my opponents is potentially going to take the party or the country in a direction that does not meet our challenges, does not take advantage of the opportunities that are available — I’m going to point it out."

John Edwards spoke at a mid-day event in Des Moines and called on candidates to answer "tough questions." Afterwards, Edwards said that barb was directed at Clinton as the Clinton campaign has admitted to planting questions at two Iowa events this year. 

"When you campaign in Iowa as I’ve now done twice or New Hampshire — early states — people expect you to stand in front of them and answer hard questions," Edwards said in answer to a reporter’s question. "They expect it to be an honest process."

The Clinton campaign admitted this weekend that two people at two separate events in Iowa had been asked by the campaign to ask a question on a specific topic. Clinton herself told the Jefferson-Jackson Day banquet-goers on Saturday that people know where she stands on the issues, but Edwards said "responsible" candidates take "hard" questions from their audiences.

"What George Bush does is plant questions and exclude people from the events and I don’t think that’s what Democrats want to see in Iowa," Edwards said.

According to Edwards, Iowans "can’t tell" where Clinton stands on many issues. "I mean, she says she’s for ending the war but she’ll continue combat missions in Iraq. She says she’s for standing up to Bush on Iraq, and she votes with Bush on the Iranian Revolutionary Guard. I mean, she stood beside me at a debate in Davenport, Iowa, and said that she was not for doing anything with the taxes for Social Security and apparently she told somebody in private that she was," Edwards told reporters.

Clinton was scheduled to campaign in Waterloo Sunday afternoon.  On Saturday evening, Clinton seemed to address the criticism being sent her way.

"Now, there are some who will say they don’t know where I stand.  Well, I think you know better than that," Clinton said.  "I stand where I have stood for 35 years.  I stand with you and with your children and with every American who needs a fighter in their corner."

Radio Iowa