JAKARTA, Indonesia — The Indonesian Parliament, under the control of emboldened political forces opposed to President-elect Joko Widodo, convened for a new five-year term on Wednesday, setting the stage for a long-term battle over the future of democracy in Southeast Asia’s most populous country.

The opposition bloc is led by Prabowo Subianto — a former army general who lost a bitterly contested presidential election to Mr. Joko in July — and controls 68 percent of the seats in the House of Representatives, the main legislative body.

Mr. Prabowo, 62, was once a son-in-law of Suharto, Indonesia’s late authoritarian president, whose military-backed regime ruled the country for 32 years until he was forced to resign amid pro-democracy demonstrations in 1998.

Despite Mr. Prabowo’s election loss three months ago, his “Red and White Coalition” — a reference to the colors of the Indonesian flag — continues to exert its influence, including orchestrating the passage last Friday of 11th-hour legislation in the previous Parliament that eliminated direct elections for mayors, district chiefs and provincial governors.