And to bring another 1440 into the discussion, KMAJ Topeka KS appears to be the station WGEM had to protect way back when, as Radio-Locator shows for WGEM's night pattern: http://radio-locator.com/cgi-bin/pat?call=WGEM&service=AM&status=L&hours=N
So to try to confirm my suspicions, I checked out the .pdf History Cards on both stations, available on the FCC's AM Query search (not all stations have been done yet) The first app for a CP for what is now KMAJ was filed in October of 1945, 1 kW-D, .5 kW-N. They amended in January 1946 to specify 5 kW day and night with the same DA pattern.
Meanwhile WGEM first filed for 1440 at Quincy with 1 kW day and night in June of 1946. I can only guess that some sort of deal was struck between KMAJ and WGEM, for on 4/28/47 and 4/29/47, respectively, both stations filed for new CPs, with KMAJ at the present-day 5 kW-D/1 kW-N and WGEM at 1 kW-U with DA. (now 5kW-D/1kW-N)
And so that's how WGEM came to have that odd "rabbit ear" night pattern with the spot between the ears pointed at Topeka.
And in the daytime (map at: http://radio-locator.com/cgi-bin/pat?call=WGEM&service=AM&status=L&hours=D) it appears that WGEM was impaired to the east due to other 1440s in Paris, IL (the current 1kw WPRS) and a station out of Bloomington/Normal that went dark around 1990. Plus a 1450 (formerly WCVS now WFMB-AM Springfield, IL).