One minute Barack Obama was schmoozing with the press pack and demonstrating his technique for kissing babies on the campaign trail, the next he was looking like a man whose pooch had turned into a rabid attack dog.
Goaded into action by months of prodding by the Clinton campaign, the once- fawning national press is lining up to take swipes at the leading Democratic candidate for the White House.
And voters are suddenly discovering that the candidate who talks like a man who walks on water, is in fact a politician who has made some questionable calls. In the midst of his most important electoral test in Texas and Ohio, he is facing renewed scrutiny that is only a foretaste of what is yet to come should he win the Democratic nomination.
He is being asked about his links to a political corruption case in Chicago; a visit he made to the home of two unrepentant members of the Weather Underground domestic terrorist group from the 1960s; his closeness to a pastor who rants about "this racist United States of America", and whether or not he is a secret Muslim.
His campaign took its most serious knock when the conservative Canadian government – a close ally of George Bush – leaked a damaging memo revealing that Mr Obama's top economic adviser had made soothing noises about his true position on the North American Free Trade Agreement that Mr Obama has relentlessly attacked on the campaign trail.
The whispering campaign that Mr Obama is a Muslim refuses to go away. When asked what she thought of the accusations, Hillary Clinton primly replied, "Well, he says he's a Christian", with a wink to the conspiracy theorists who cannot accept that a man with the middle name Hussein may be a Christian.
This has so destabilised Mr Obama that he found himself confessing to an audience this week that he was not only born a Christian but that he "prays to Jesus" every night and tries to go to church as often as possible. Mr Obama has been able to bat away many of the questions about his prior life in the rough and tumble world of Chicago politics.
Now he is facing accusations that he visited the home of two well-known left-wing figures in his Hyde Park neighbourhood: William Ayers and Bernardine Dohrn.
Both are political activists, but what has caught the eye of the national press is that they are both unrepentant throwbacks to the radical and violent 1960s anti-Vietnam War movement. "I don't regret setting bombs; I feel we didn't do enough," one of them told an interviewer in 2001.
It will all be grist to the mill for Republicans should Mr Obama become the nominee.
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