diff --git a/Lib/heapq.py b/Lib/heapq.py
index 23f8be5..47326f3 100644
--- a/Lib/heapq.py
+++ b/Lib/heapq.py
@@ -233,7 +233,7 @@
     while childpos < endpos:
         # Set childpos to index of smaller child.
         rightpos = childpos + 1
-        if rightpos < endpos and heap[rightpos] < heap[childpos]:
+        if rightpos < endpos and heap[rightpos] <= heap[childpos]:
                 childpos = rightpos
         # Move the smaller child up.
         heap[pos] = heap[childpos]