IBD is definitely going to show a major swing towards Clinton right before the end so they can keep up their "most accurate pollster" shtick, mark my words.
2012 is not a good example because most polls showed the race as dead heat so I checked out 2008.
IBD herded hard-core in 2008. They were, on average, showing lower margin for Obama only to join the crowd toward the end.
Check out 2008 numbers for the last few weeks.
Diageo/Hotline 10/20 - 10/22 769 LV 3.5 48 43 Obama +5
Reuters/C-SPAN/Zogby 10/20 - 10/22 1206 LV 2.9 52 40 Obama +12
ABC News/Wash Post 10/19 - 10/22 1335 LV 2.5 54 43 Obama +11
IBD/TIPP 10/18 - 10/22 1060 LV 3.5 45 44 Obama +1GWU/Battleground 10/16 - 10/22 1000 LV 3.5 49 45 Obama +4
FOX News 10/20 - 10/21 936 LV 3.0 49 40 Obama +9
CBS News/NY Times 10/19 - 10/22 771 LV -- 52 39 Obama +13
ABC News/Wash Post 10/23 - 10/26 1314 LV 2.5 52 45 Obama +7
Pew Research 10/23 - 10/26 1198 LV 3.5 53 38 Obama +15
IBD/TIPP 10/22 - 10/26 824 LV 3.5 47 44 Obama +3GWU/Battleground 10/20 - 10/26 1000 LV 3.5 49 46 Obama +3
Newsweek 10/22 - 10/23 882 LV 4.0 53 41 Obama +12
But somehow their average became more realistic toward the end.
Rasmussen Reports 11/1 - 11/3 3000 LV 2.0 52 46 Obama +6
Reuters/C-SPAN/Zogby 11/1 - 11/3 1201 LV 2.9 54 43 Obama +11
IBD/TIPP 11/1 - 11/3 981 LV 3.2 52 44 Obama +8FOX News 11/1 - 11/2 971 LV 3.0 50 43 Obama +7
NBC News/Wall St. Jrnl 11/1 - 11/2 1011 LV 3.1 51 43 Obama +8