Under instructions from the campaign, Biden kept his speeches succinct and tried to avoid offhand remarks, such as one he made about Obama's being tested by a foreign power soon after taking office, which had attracted negative attention. Privately, Biden's remarks frustrated Obama. "How many times is Biden gonna say something stupid?" he asked. Obama campaign staffers referred to Biden blunders as "Joe bombs" and kept Biden uninformed about strategy discussions, which in turn irked Biden. Relations between the two campaigns became strained for a month, until Biden apologized on a call to Obama and the two built a stronger partnership. Publicly, Obama strategist David Axelrod said Biden's high popularity ratings had outweighed any unexpected comments. Nationally, Biden had a 60% favorability rating in a Pew Research Center poll, compared to Palin's 44%.