The Corporate Survey found 60% of firms hoped the ruling bloc will keep the number of seats it holds now, and 17% want it to win more.

Just 20% hoped Abe's coalition will lose seats and 3% hoped it will lose its majority, according to the survey conducted July 1-12 for Reuters by Nikkei Research.

The results chimed with recent media surveys which showed Abe's Liberal Democratic Party-led (LDP) coalition is on track to keep its majority in the chamber.

Together with like-minded allies, Abe's coalition could also keep the two-thirds majority needed to achieve his goal of revising the pacifist, post-war constitution to further legitimise the military.

Despite the overwhelming support suggested in the survey, it also showed companies were almost split on Abe's performance so far in delivering economic growth and labour reform.

Two-thirds of the companies appreciated Abe's diplomacy and security policy, reflecting Japan's hosting of a summit of the Group of 20 major economies in Osaka last month.

However, the same proportion of firms gave a low evaluation of Abe's welfare policy amid worries about the pension system and a sales tax hike slated for October.

"Worries about the future are growing," a retailer manager wrote in the survey.

Those firms who hailed Abe's diplomacy praised his efforts to keep a favourable relationship with U.S. President Donald Trump, improve ties with China and take a resolute attitude against South Korea, but some voiced concerns.

"Risks are high on his diplomacy that clings to Trump. He has tried many things but nothing has produced concrete results. That shows the reality of Abe's diplomacy," a machinery maker manager wrote in the survey.

Asked who should be the next prime minister, 37% of firms said Abe should stay on, followed by telegenic young lawmaker Shinjiro Koizumi at 21%, the survey showed.

Chief Cabinet Secretary Yoshihide Suga took 11% and former defence minister Shigeru Ishiba had 10%. Yukio Edano, the head of Japan's biggest opposition party, garnered just 2%.

The Corporate Survey canvassed 504 big and midsize companies, of which around 240 firms responded on condition of anonymity.

(Reporting by Tetsushi Kajimoto; Editing by Kim Coghill)

By Tetsushi Kajimoto