Hawaii voters have not contemplated such a dizzying array of election choices in years. With reapportionment, all the state legislative seats are up for a decision. There’s a super-heated Honolulu mayoral race with implications for future development, congressional pairings and, oh, let’s not forget the multibillion-dollar marathon wrestling match with four years in the White House as a prize.

But the argument could be made that the retirement of U.S. Sen. Daniel Akaka has presented the electorate with its most consequential political opening. Whenever the senior Sen. Daniel Inouye ends his long tenure on Capitol Hill, his replacement, at least initially, will become junior to whoever wins the general election Nov. 6.

There’s opposition from multiple candidates in the Republican primary, but the well-funded campaign of former Gov. Linda Lingle is virtually assured success there.

So the winner of the Democratic primary — U.S. Rep. Mazie Hirono and former Congressman Ed Case are the dominant contenders — will have a real shot at being Hawaii’s next senior senator at some point. He or she would start at the bottom of the all-important seniority list, but in time could accrue some real standing.

Let’s face it: The half-century-old pattern in Hawaii politics indicates that once the isles send someone to the U.S. Senate, they tend to stay there for a very long time.

That’s why the public really should home in on this campaign and get the best reading they can on the candidates. At this juncture, all the action is in the Democratic primary.

There have been too few of these to date, but in last week’s face-to-face encounters between Hirono and Case, a line of demarcation between their positions started to emerge.

Case and Hirono did appear together at a bipartisan forum before the Hawaii Lodging & Tourism Association May 29, but that was not as wide-ranging topically as the more recent events.

The series of three started on Tuesday at the Maui Beach Hotel, with a debate sponsored by AARP-Hawaii. Not surprisingly the questions there focused largely on the entitlements of Medicare and Social Security on which senior citizens rely heavily.

But the theme was resurrected in the meetups that followed: the Hawaii Public Radio debate on Wednesday and a face-off on Thursday on PBS-Hawaii, with Hirono firmly advocating for increasing revenues and Case advocating at least some curb, for future beneficiaries, on benefits, primarily by delaying when they could be drawn.

In general, both seemed comfortable on their respective sides of the divide on fiscal policy.

Case, who has described himself as a "blue dog" Democrat, frowned at the idea of President Barack Obama’s infrastructure investment plan, the American Jobs Act. Hirono, true to her liberal principles, argued forcefully that "stimulus" should not be seen as a dirty word in an economy that took a beating to its very foundations in 2008.

There was also disagreement on American military actions in the Middle East, with both wanting to exit Afghanistan but Case more accepting of the drone program in the region.

These issues encapsulate important elements of the rhetorical battle that has raged nationally. They’re central to the decision that voters have to make, and the people need to see more of the discussion between two of the pre-eminent candidates.

The format is important. A debate is superior to a forum, because the questioning is propelled primarily by the people most motivated to draw out a clear answer: the candidates themselves. And it helps having the back-and-forth moderated by one or more informed, third-party inquisitors, usually from the news media, who are in a position to hold the debaters accountable for their statements.

A canceled forum, which was to have been hosted by the Oahu Democrats, may or may not be rescheduled. Either way, Case is right to push his opponent hard to have more debates before the Aug. 11 primary, and Hirono, who showed she gained more polish and ease with the past years of experience, should not hang back.

It should serve the interest of each candidate to hold a rival’s feet to the fire. It certainly serves the voters’ interest … and isn’t that the whole point of running for office?