Airing his concerns about Obama as a presidential nominee, Shaheen told the Washington Post, 'The Republicans are not going to give up without a fight... and one of the things they're certainly going to jump on is his drug use.'
Shaheen added that, since Obama's background was relatively unknown, it would 'open the door' to further questions. 'It'll be, 'When was the last time? Did you ever give drugs to anyone? Did you sell them to anyone?'... There are so many openings for Republican dirty tricks. It's hard to overcome.'
These last few days have seen the Clinton campaign quietly focus on Obama's drug use, detailed in his 1996 memoir, Dreams From My Father: A Story of Race and Inheritance, but Shaheen's remarks have been seen as out of line.
And the fire-fighting has already begun. Even as Clinton campaign spokesman Phil Singer issued a statement saying Shaheen's remarks 'were not authorised or condoned by the campaign,' Shaheen resigned as co-chair.
In his statement, Shaheen said, 'I would like to reiterate that I deeply regret my comments and say again that they were in no way authorised by Senator Clinton or the Clinton campaign... I made a mistake and in light of what happened, I have made the personal decision that I will step down as the co-chair of the Hillary for President campaign. This election is too important and we must all get back to electing the best qualified candidate who has the record of making change happen in this country. That candidate is Hillary Clinton.'
Did you know? Shaheen’s wife, former New Hampshire governor Jeanne Shaheen, is running for the US senate, elections for which will be held next year.
Image: Democratic candidate for US President, US Senator Hillary Clinton speaks as US Senator Joe Biden and US Senator Chris Dodd laugh during The Des Moines Register Democratic presidential debate.
Photograph: John Gaps III-Pool/Getty Images
Also read: The twists and turns in Presidential elections
External link: Clinton co-chair resigns over Obama drug remark