As voters go to the polls tomorrow in Masachusetts, we are on the cusp of a major election upset by Republican Scott Brown. To illustrate how rapidly the ground has shifted on this campaign, let’s look back at the “rolling averages” of polls taken in the last few days:

January 13: Coakley 50%, Brown 43%

January 14: Coakley 48%, Brown 45%

January 15: Coakley 46%, Brown 48%

January 16: Coakley 45%, Brown 48%

January 18: Coakley 44%, Brown 51%

For the results today, there were actually six polls conducted over the Friday-Sunday time period. In five of those six polls, Republican Scott Brown consistently garnered 51-52% support, while Democrat Martha Coakley’s support varied from 41-46%. In other words, the question now is how far above 50% Brown will go when the vote is counted tomorrow night.

One final thought about the race: while we recently predicted a 51-47% Scott Brown victory, a recent Insider Advantage poll that analyzed the Brown/Coakley numbers. In that poll, it showed that Republicans are 86-10% for Brown, Independents are 69-28% for Brown, and Democrats are 71-24% for Coakley. If we were to apply these percentages to the Massachusetts voter population and assume that they turn out in proportion to their numbers (which is 50% Independent, 37% Democrat, and 12% Republican) in the voter rolls, Scott Brown would lead 54-41%. A victory of this size would nearly be unprecedented in recent Masachusetts history. In fact, in the last 30 years of statewide elections in Masachusetts, only one Republican (William Weld, in his 1994 gubernatorial re-election) has exceeded 51% statewide – even the 1984 Reagan landslide only got him 51% of the vote in Masachusetts.