Read the full Gallup poll

Just over a week ago, Hillary Clinton was leading Barack Obama by 20 points, but in an updated Jan. 27-29 survey by Gallup, Obama has closed the gap to 6 points, with Clinton ahead 42 percent to 36 percent. One difference in this poll compared to the Gallup we reported earlier is that it includes two full days instead of one in interviewing that took place after the endorsement of Sen. Edward Kennedy. Another new factor to follow in the next poll is the effect of John Edwards decision to drop out of the race. Edwards was polling at 12 percent.

Among Republicans, John McCain leads Mitt Romney 32 percent to 21 percent, and it remains to be seen to whom supporters of Rudy Giuliani, at 11 percent, will turn when he drops out and endorses McCain as expected. Mike Huckabee registered 18 percent. McCain has to hope his victory starts the campaign cash flowing, because his latest report to the Federal Elections Commission showed that he closed out 2007 with only $2.9 million cash-on-hand.

The margin of error is 3 percent.