How can Republicans defeat Hillary Clinton in 2016? Bill O'Reilly asked Charles Krauthammer what the GOP strategy should be, as it becomes increasingly likely that Clinton will become the nominee.

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Krauthammer believes Hillary will be nominated in a "coronation," but points to narrowing poll numbers between the former First Lady and possible Republican rivals.

He repeated his call for the GOP to highlight Clinton's lack of achievements as secretary of state. Krauthammer explained what happened at a recent forum when Clinton was asked to name her "proudest achievement as secretary of state."

"She could not answer the question. She fumbled around and you know what she ended up saying? 'I handed off the baton.' Can you tell me if there's any great track and field star who is remembered for handing off the baton? asked Krauthammer, defying O'Reilly to name one achievement.

He called out Clinton for founding the naive "reset" policy with Russia, though O'Reilly countered that on the campaign trail he believes Clinton will "repudiate" much of the Obama administration's policies. Krauthammer answered that in order to become president, a candidate needs to have worthy credentials.

"Why should she become President of the United States, other than she married a man who became president? Krauthammer asked, arguing she will try to run on the "reflected glory of the 90's."

O'Reilly predicted Clinton will position herself as the "champion of women and children." Krauthammer recalled that he felt "proud to be an American" on the day of Barack Obama's inauguration, but questions whether Americans will vote for Hillary simply to make history again.

"Given the record of this amateur who came into the presidency unprepared and the record he's going to leave behind, I'm not sure the country will want to elect a second president simply to set a precedent," said Krauthammer, adding that the Republican nominee will need to focus on Benghazi, Russia and Clinton's lack of accomplishments at the State Department.

O'Reilly pointed to Bill Clinton as a big factor, saying voters will believe that he's going to be involved in decision-making if Hillary wins the White House and the former president will also act as "attack dog" during the campaign.

Watch the full discussion above.

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