Portland is eliminated from first place.

To show that Portland is eliminated from first place, we start with the current conference standings:
            Team	W	L	GL	PCT	GB
   Oklahoma City	51	15	16	0.773	0.0
     San Antonio	48	17	17	0.738	2.5
         Houston	40	24	18	0.625	10.0
       LA Lakers	40	25	17	0.615	10.5
       Minnesota	40	25	17	0.615	10.5
          Denver	39	26	17	0.600	11.5
         Phoenix	38	27	17	0.585	12.5
     LA Clippers	32	32	18	0.500	18.0
    Golden State	32	33	17	0.492	18.5
        Portland	31	35	16	0.470	20.0
         Memphis	23	41	18	0.359	27.0
          Dallas	21	44	17	0.323	29.5
     New Orleans	21	45	16	0.318	30.0
            Utah	20	45	17	0.308	30.5
      Sacramento	16	50	16	0.242	35.0
           Total	492	484	254

Portland can finish the season with at most 31 + 16 = 47 wins and will finish the season behind the following teams:
Oklahoma City has already won 51 games.
San Antonio has already won 48 games.