When the GOP convention opened on September 1st 2008, with the first day cancelled like the 2012 Tampa conventions, candidate Obama had a 4 and a half point lead over John McCain 48.8 to 44.3.
On the first real day of the convention McCain was behind Obama by a huge 6.4 points 49.2 to 42.8
In four days from Sarah Palin's vice-presidential nomination acceptance speech on September 3rd , on September 7th, the McCain/Palin team went into the lead by 1 point 46.7 to Obama's 45.7
On the 9th day from the opening of the convention the McCain/Palin lead was 2.4 points over Obama and huge turnaround from the 6.4 point deficit.
Thus Palin's acceptance speech saw a 9% increase in support from the night of her address for McCain/Palin
and at its height the McCain/Palin convention bounce was 3.7 points.
These are the figures that Romney/Ryan would have to be compared with. The initial results, as far as 17 million fewer viewers watching Paul Ryan's acceptance speech, are not promising for them. On September 7th McCain/Palin were in the lead with a 2.3 point convention bump
HERE ARE THE SEVEN DAYS FROM THE OPENING OF THE ROMNEY CONVENTION ACCORDING TO RCP AVERAGES (INCLUDING GALLUP) ON REAL CLEAR POLITICS.ON A SEVEN DAY COMPARISON:
ROMNEY IS STILL BEHIND AND HIS CONVENTION BUMP IS 0.4 POINTS