Nobody saw this coming.

Barack Obama, running on a theme of “change,” has not scored a public relations bonanza with his decision to nominate for vice president Joe Biden, a senator who has been in office since Richard Nixon was president, instead of Hillary Clinton, who has been in office since November 7, 2000.

Sixty-six percent of Clinton supporters, registered Democrats who want Clinton as the nominee, are now backing Obama. That’s down from 75 percent in the end of June. Twenty-seven percent of them now say they’ll support McCain, up from 16 percent in late June.

And the more Clinton supporters think through what just happened, I am guessing, the more will scratch their heads about Obama’s choice for VP.