The very best poll is on an election day, and on election day, 2008, Barrack Obama had a whopping 53% following. That's huge.
Tracking for today (Wednesday) shows 24% of the nation's voters strongly approve of the way Barack Obama is performing as president. Obama currently has a 46% approval rating, not that bad, I suppose, meaning that 46% of the electorate at least "somewhat" approves of the president's performance.
At this same time, 19 months into his presidency, George Bush had an approval rating of just over 60%, (down from a high of 92% after the attack on New York) It took Bush longer to drop below 50% approval rating than it has Obama to underachieve this, but Bush continued to drop throughout the remainder of his presidency. Obama still has lots of time left to recover, probably.
In the "Well, DUH!" department: 70% of registered voter poll respondents say they believe congress takes payments in return for their votes. In fact, 56% say they believe THEIR congressman is on the take.