With an Upper House election in July and a tax hike planned for October, murmurs fueled by comments from top ruling party lawmakers that Prime Minister Shinzo Abe may call a snap Lower House general election this summer have been reverberating through the nation's political and financial circles.

For the ruling coalition, a snap election would be a major political gamble because it would put its current supermajority of more than two-thirds in both chambers at risk.

But for Abe, the risk may be worth the potential reward because there may be no better time for him to call a general election than this summer, given an expected economic slowdown in the fall, Cabinet's high approval ratings and a tight political schedule over the next two years, political observers say.