(Bloomberg) — Joe Biden said Friday he would not rule out appointing donors as ambassadors, but wouldn’t make decisions about those roles based on someone’s financial contributions.“Nobody in fact will be appointed by me based on anything they contributed,” he told a group of reporters aboard his “No Malarkey” bus in Decorah, Iowa.“But, for example, you have some of the people who are out there that are prepared to in fact, that are fully qualified — head of everything from being the ambassador to NATO to be the ambassador to France or any other country — who may or may not have contributed, but that will not be any basis upon which I in fact would appoint anybody.”Other Democratic presidential candidates, including Senator Elizabeth Warren, have criticized the longstanding practice of appointing donors to governmental positions. Warren, who has sworn off high-dollar fundraisers, has vowed to not nominate wealthy contributors as ambassadors.In a wide-ranging 20-minute interview, Biden also defended his response to an Iowa voter who confronted him Wednesday over his son’s work in Ukraine, which has come into sharp focus during the U.S. House impeachment investigation of President Donald Trump. He said he wanted to keep the focus on Trump, but reacted because the man made accusations that were false.Biden said his son did nothing wrong and referred to a statement by Hunter Biden that he exercised “poor judgment” in joining the board of the Ukrainian energy company Burisma Holdings.”My son speaks for himself,” the former vice president said. “He’s a 47-year-old man. He didn’t do anything wrong.”Joe Biden, who is at the end of an eight-day bus tour across Iowa, again spoke about the need for bipartisan cooperation. He emphasized the vital role that the two-party system plays in American democracy, and the importance of having a robust Republican Party.“I’m really worried that no party should have too much power,” he said. “You need a countervailing force.”He added: “You can’t have such a dominant influence that then you start to abuse power. Every party abuses power if they have too much power.”Biden also touted his ability to help other Democrats get elected, as he argued why he is best suited to bring about gains for party candidates as the presidential nominee.Biden, who often cites polls in swing states that show him defeating Trump, said the requests from candidates in swing districts for him to campaign on their behalf in the midterms is evidence of his appeal.“I don’t have to go out and look at a poll,” he said. “Just go into those states. You can feel it. You can taste it.”(Michael Bloomberg is also seeking the Democratic presidential nomination. Bloomberg is the founder and majority owner of Bloomberg LP, the parent company of Bloomberg News.)To contact the reporter on this story: Tyler Pager in Decorah, Iowa at [email protected] contact the editors responsible for this story: Wendy Benjaminson at [email protected], Max Berley, John HarneyFor more articles like this, please visit us at bloomberg.com©2019 Bloomberg L.P.