London, Sept. 10 -- British Prime Minister Boris Johnson has lost Parliament. But he could still win a general election if enough voters approve of his determination to make Britain's departure from the European Union a reality.

The U.K. leader who took office in July failed spectacularly in his first encounter with Parliament, losing six important votes before suspending the legislature for an unexpected five weeks during a crucial period in Britain's political life. He was unable to convince enough lawmakers to back his call for an early national election, which he hoped would give him a more pliant group of lawmakers.

Despite his inability to get a general election set for mid-October - Parliament voted him down twice on that score -...