On this day, September 27th 2007, then Senator Obama had an average 23.3 support polling average nationally, while Clinton held a 17 point lead with a solid 40.5% support (RCP). Interesting history nonetheless, but let's dig a bit deeper.
Today in History:
My, my this chart looks awfully similar to another one. Which one could it be similar to? Well how about 2015.
If you look at the chart and compare it to the other one Bernie Sanders is actually outperforming then Senator Obama's polling average. Sanders only has a 13 point gap compared to Obama who had a 17 point gap on this day.
Keep in mind that at this point in time there had already been about a dozen debates. Furthermore, in the chart from 2007, the polling stayed fairly consistent nationally the entire time up until Iowa, this time the trend is very linearly up for Bernie and down for Clinton... Bernie is doing better.
Some may argue that its not the same thing because there were other big candidates in the race at this point. Edwards was in fact in the race but was polling at or around the same exact place Biden is right now, so the dynamics are very similar.
The debate will be a turning point, and if Bernie does well he could very well catch up to Hillary nationally, and at that point its anyone's game. It's been done before and it can be done again-- anyone who says its not possible is being intellectually dishonest.