The Liberal Democratic Party, which led Japan for most of the post-World War II era until it was dumped as the economy fizzled in 2009, won 294 seats in the 480-seat lower house of parliament in Sunday's nationwide elections, according to media reports. Official results were expected later Monday.
With the elections over, a vote among the members of parliament to install the new prime minister is expected as soon as Dec.
"We won more seats than even we expected," Abe, 58, said Monday. "We have a very heavy responsibility."
Outgoing Prime Minister Yoshihiko Noda announced his resignation late Sunday, calling the election results "severe" and acknowledging his party failed to live up to the nation's high expectations.
His Democratic Party of Japan reportedly won only 57 seats. Among its casualties were eight Cabinet ministers—the most lost in an election since World War II.
Economic issues, including plans to raise taxes and other measures to bolster Japan's underperforming economy, were the top concerns among voters.
Abe, who would be Japan's seventh prime minister in 6 1/2 years, will likely push for increased public works spending and lobby for stronger moves by the central bank to break Japan out of its deflationary trap.
Stock prices soared Monday morning to their highest level in more than eight months, reflecting hopes in the business world that the LDP will be more effective in its economic policies than the Democrats were.
Although the election was the first since the March 11, 2011, earthquake, tsunami and nuclear disasters, atomic energy—which the LDP conditionally supports—ended up being a side issue, though polls showed that about 80 percent of Japanese want to phase it out completely.
Instead, Abe and his party stressed national security amid an ongoing dispute with China over a group of small uninhabited islands that both nations claim.
That kind of tough talk resonates with some voters who fear their country is falling too far behind China's rising economic and military clout, but it could also deepen a rift between Tokyo and Beijing that has already begun to sour diplomatic ties and trade.
Abe is known as a hawk on China relations—which could mean more friction with Japan's giant neighbor and key trading partner.
During his previous tenure as prime minister, Abe pursued a nationalistic agenda, pressing for more patriotic education and upgrading the defense agency to ministry status. The LDP wants to revise Japan's pacifist constitution to strengthen its Self-Defense Forces and, breaching a postwar taboo, designate them as a "military."
It also proposes increasing Japan's defense budget and allowing Japanese troops to engage in "collective self-defense" operations with allies that are not directly related to Japan's own defense.
But with the economy in more dire straits, it remains to be seen how Abe will behave this time around.
As the results came in Sunday night, he acknowledged that the outcome of the elections was as much—if not more—of a protest against the status quo as it was an endorsement of his party's platform.
The LDP will stick with its longtime partner New Komeito, backed by a large Buddhist organization, to form a coalition government, party officials said. Together, they now control 325 seats, securing a two-thirds majority that would make it easier for the government to pass legislation.
A dizzying array of more than 12 parties, including several news ones, contested, some with vague policy goals. The most significant new force is the right-leaning, populist Japan Restoration Party, which won 54 seats, according to NHK.
The party is led by the bombastic nationalist former Tokyo Gov. Shintaro Ishihara and lawyer-turned Osaka Mayor Toru Hashimoto—polarizing figures with forceful leadership styles. Ishihara is another hawk on China, having stirred up the latest dispute with Beijing by proposing Tokyo buy the islands from their private Japanese owners and develop them.
The anti-nuclear Tomorrow Party—formed just three weeks ago—captured only nine seats, according to NHK. Party head Yukiko Kada said she was very disappointed to see the LDP, the original promoter of Japan's nuclear energy policy, make such a big comeback.
Associated Press writers Elaine Kurtenbach, Mari Yamaguchi and Eric Talmadge contributed to this report.