By Elaine KurtenbachTOKYO -- Japanese broadcasters projected that Prime Minister Shinzo Abe's ruling coalition won a majority of seats in the upper house of parliament in elections Sunday, giving it control of both chambers for the first time in six years. The victory is seen as an endorsement of Abe's economic program, which has helped spark a tentative recovery, and gives him a legislative mandate to pursue difficult economic changes that he has promised to help sustain growth in the long run. The victory in the elections, where half the seats in the 242-member upper house were up for grabs, offers Abe more leeway to advance nationalistic goals that could further strain testy relations with China and South Korea. It is a vindication for Abe, who lost upper house elections in 2007 during his previous stint as prime minister. Based on exit polls, public broadcaster NHK predicted that Abe's Liberal Democratic Party and its coalition partner, New Komeito, won a combined 71 seats, giving them a total of 130 seats in the chamber, more than the 122 needed for a majority. The Liberal Democrats were projected to take at least 61 seats, which together with the 50 they held before the vote would give them 111, short of an outright majority. Official results weren't expected until early Monday. Voter turnout was reported to be low, suggesting a lack of public enthusiasm. Abe says his top priority is to sustain the economic recovery that, helped along by aggressive monetary and fiscal stimuli since he took office in late December, has lifted share prices, boosted business confidence and helped exporters by weakening the yen. Japan's long-term growth will depend on sweeping changes to increase competitiveness and help cope with Japan's rapidly graying population and soaring national debt. Such changes, long overdue, are bound to prove difficult even with control of both chambers of the parliament. The LDP's vice president, Masahiko Komura, welcomed the early projections. "Obviously, the results so far show that voters want a stable government," Komura said in a live TV interview with NHK.