"We will continue to push Abenomics steadily in order to live up to their expectations," he said.
The gain in parliamentary strength will help relieve the gridlock of past years, but is no guarantee of smooth sailing for the ruling bloc.
Abe faces a decision this fall on whether to follow through on raising the sales tax next April from 5% to 8%, a move needed to shore up Japan's public finances, but one that many worry will derail the recovery.
After more than two decades of economic doldrums, the Japanese public has grown weary of political bickering and ineffectual leadership. Bereft of an effective, united political opposition, it has opted for the perceived safety of the Liberal Democrats, who have ruled Japan for most of the past seven decades.
"I want them to carry on doing their best as the economy seems to be picking up," Naohisa Hayashi, a 35-year-old man who runs his own business, said after casting his ballot at a downtown Tokyo polling station.
The Liberal Democrats' "Recover Japan" platform calls a strong economy, strategic diplomacy and unshakable national security under the Japan-U.S. alliance, which allows for 50,000 American troops to be stationed in Japan.
The party also favors revising the country's pacifist constitution, drafted by the United States after World War II, to give Japan's military a larger role -- a message that alarms the Chinese government but resonates with some Japanese voters troubled by territorial disputes with China and South Korea and widespread distrust of an increasingly assertive Beijing.
Abe has upset both neighbors by saying he hopes to revise a 1995 apology by Japan for its wartime aggression and questioning the extent to which Korean, Chinese and other Asian women were forced to provide sex for Japanese soldiers before and during World War II.
Revising the constitution would require two-thirds approval by both houses of parliament and a national referendum. Polls show the public is less interested in such matters than in reviving the economy and rebuilding areas of northeastern Japan devastated by the March 2011 earthquake and tsunami.