Revised Trend Models with House Effects

Includes five additional polls released between 10/25 and 10/28.

146 Likely Voter Polls from Pollster (7/1-10/28) 
Dependent variable: Obama Lead over Romney
Ordinary Least Squares

                 coefficient   std. error   t-ratio   p-value 
  ------------------------------------------------------------
  const           5.72235      0.579939      9.867    1.54e-17 ***
  Debate1        −5.47401      1.05759      −5.176    8.24e-07 ***

  Trends
  Pre-Debate     −0.0514766    0.00937824   −5.489    2.00e-07 ***
  Post-Debate    −0.0124666    0.0424105    −0.2940   0.7693

  House Effects
  Rasmussen      −2.35773      0.437616     −5.388    3.18e-07 ***
  Gallup         −4.34481      1.18503      −3.666    0.0004   ***
  YouGov/Econ     1.80215      1.02690       1.755    0.0816   *
  ARG            −1.93337      0.844044     −2.291    0.0236   **
  DemCorps        2.15593      1.03252       2.088    0.0387   **
  UTech/NJ       −3.81771      2.00889      −1.900    0.0596   *
  NPR             2.74136      1.44450       1.898    0.0599   *
  Allstate/NJ     3.74853      2.00311       1.871    0.0635   *
  Reason/Rupe     3.85149      2.00263       1.923    0.0566   *
  JZAnalytics     2.65474      0.790120      3.360    0.0010   ***

Mean dependent var   1.075342   S.D. dependent var   3.055996
Sum squared resid    519.2214   S.E. of regression   1.983304
R-squared            0.616576   Adjusted R-squared   0.578815
F(13, 132)           16.32820   P-value(F)           1.13e-21

For models like this with Rasmussen included, I created separate pre- and post-debate trends and tested whether each significantly differs from zero.  This model shows that the trend before the Denver debate was significant favorable to the President, but since the debate the race has stagnated.