diff --git a/patroni/api.py b/patroni/api.py
index de121b2e..73cdb14c 100644
--- a/patroni/api.py
+++ b/patroni/api.py
@@ -92,7 +92,7 @@ class RestApiHandler(BaseHTTPRequestHandler):
             return response.get('role') == 'replica' and not patroni.noloadbalance
 
         if cluster:  # dcs available
-            if cluster.leader and cluster.leader.name == patroni.postgresql.name:  # is_leader
+            if patroni.ha.is_leader():
                 status_code = 200 if 'master' in path else 503
             elif 'role' not in response:
                 status_code = 503
diff --git a/patroni/ha.py b/patroni/ha.py
index f386bb00..e6a9797d 100644
--- a/patroni/ha.py
+++ b/patroni/ha.py
@@ -57,6 +57,8 @@ class Ha(object):
         self.dcs = patroni.dcs
         self.cluster = None
         self.old_cluster = None
+        self._is_leader = False
+        self._is_leader_lock = RLock()
         self._was_paused = False
         self._leader_timeline = None
         self.recovering = False
@@ -87,6 +89,14 @@ class Ha(object):
     def is_paused(self):
         return self.check_mode('pause')
 
+    def is_leader(self):
+        with self._is_leader_lock:
+            return self._is_leader
+
+    def set_is_leader(self, value):
+        with self._is_leader_lock:
+            self._is_leader = value
+
     def load_cluster_from_dcs(self):
         cluster = self.dcs.get_cluster()
 
@@ -98,7 +108,9 @@ class Ha(object):
         self._leader_timeline = None if cluster.is_unlocked() else cluster.leader.timeline
 
     def acquire_lock(self):
-        return self.dcs.attempt_to_acquire_leader()
+        ret = self.dcs.attempt_to_acquire_leader()
+        self.set_is_leader(ret)
+        return ret
 
     def update_lock(self, write_leader_optime=False):
         last_operation = None
@@ -108,6 +120,7 @@ class Ha(object):
             except Exception:
                 logger.exception('Exception when called state_handler.last_operation()')
         ret = self.dcs.update_leader(last_operation)
+        self.set_is_leader(ret)
         if ret:
             self.watchdog.keepalive()
         return ret
@@ -981,6 +994,7 @@ class Ha(object):
             logger.error('Cancelling bootstrap because watchdog activation failed')
             self.cancel_initialization()
         self.dcs.take_leader()
+        self.set_is_leader(True)
         self.state_handler.call_nowait(ACTION_ON_START)
         self.load_cluster_from_dcs()
         return 'initialized a new cluster'
diff --git a/tests/test_api.py b/tests/test_api.py
index 29bcabb4..ae0f1632 100644
--- a/tests/test_api.py
+++ b/tests/test_api.py
@@ -51,6 +51,10 @@ class MockHa(object):
     state_handler = MockPostgresql()
     watchdog = MockWatchdog()
 
+    @staticmethod
+    def is_leader():
+        return False
+
     @staticmethod
     def reinitialize(_):
         return 'reinitialize'
@@ -152,7 +156,7 @@ class TestRestApiHandler(unittest.TestCase):
             MockRestApiServer(RestApiHandler, 'GET /synchronous')
         with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={'role': 'replica'})):
             MockRestApiServer(RestApiHandler, 'GET /asynchronous')
-        MockPatroni.dcs.cluster.leader.name = MockPostgresql.name
+        MockPatroni.ha.is_leader = Mock(return_value=True)
         MockRestApiServer(RestApiHandler, 'GET /replica')
         MockPatroni.dcs.cluster = None
         with patch.object(RestApiHandler, 'get_postgresql_status', Mock(return_value={'role': 'master'})):
diff --git a/tests/test_patroni.py b/tests/test_patroni.py
index d3269798..71bac6e5 100644
--- a/tests/test_patroni.py
+++ b/tests/test_patroni.py
@@ -103,6 +103,7 @@ class TestPatroni(unittest.TestCase):
 
     @patch('patroni.config.Config.save_cache', Mock())
     @patch('patroni.config.Config.reload_local_configuration', Mock(return_value=True))
+    @patch('patroni.ha.Ha.is_leader', Mock(return_value=True))
     @patch.object(Postgresql, 'state', PropertyMock(return_value='running'))
     @patch.object(Postgresql, 'data_directory_empty', Mock(return_value=False))
     def test_run(self):