President Desi Bouterse, a former military leader convicted in 1999 in the Netherlands of drug trafficking, appeared to be on course for a second term in Suriname after his party won a slim majority in Monday’s parliamentary elections, according to preliminary results Tuesday. Mr. Bouterse’s National Democratic Party won 26 or 27 seats in the 51-member assembly, according to the unofficial tally, and the opposition coalition, on track to take 17 or 18 seats, acknowledged defeat. Mr. Bouterse’s charismatic style and social welfare policies seemed to have won over voters. After his conviction in the Netherlands, he remained free, benefiting from Suriname’s lack of an extradition treaty with its former colonial ruler.