In politics, it's not just a matter of who loves you, but how much they love you.

That is, it's great to have big-time popularity. But it's entirely another to translate that affection into the kind of vote totals that will propel you into office.

That's a lesson the campaign of Democratic presidential candidate Barack Obama has already taken to heart and has fully integrated into its November election strategy.

And it is a lesson Honolulu Mayor Mufi Hannemann was painfully taught once again in the Sept. 20 primary election here.

Put briefly: It is all about turnout.

Let's start with Obama. The Hawai'i-born Democrat has energized the so-called "youth vote" like no candidate has in years. The problem is, young people are notoriously unlikely to go the polls, at least by comparison with their more settled elders. They just don't have as big a stake in things.

Obama's people know that their opponent, Republican John McCain, is particularly strong among high-turnout demographics including Republicans, more mature voters and the more affluent. For better or worse, McCain doesn't have the "youth turnout" problem.

So the Obama campaign is using every electronic and Web-based trick in its bag to get young people to vote. The campaign has amassed a huge database of cell phone numbers, Internet addresses and the like. Those electronic lines will be lighting up like a Christmas tree between now and Nov. 4, reminding distracted young people to vote, vote, vote.

Locally, the Hannemann campaign does not have that level of sophisticated outreach, nor did it appear there would be any need for it. But the primary results make it clear that he needs to do a better job — not of winning the affection of potential voters, but in getting them to act on that affection.

Advertiser government writer Derrick DePledge did a fascinating analysis this week on the district-by-district vote in the primary, where Hannemann just barely failed to reach the winning 50 percent mark.

The basic story is that Hannemann tended to do relatively better in districts with the lowest turnout. If just a few more of the districts where the majority preferred Hannemann had turnout numbers merely as good as the county-wide average, he would have won outright in the primary.

This means his task for the general election will be to stir up and turn out folks in those areas — such as along the Leeward Coast — where he is particularly popular.

Prediction: If you are a registered voter who lives anywhere from say, Kalihi to Wai'anae, expect to be hearing frequently from the Hannemann campaign in the next several weeks.

Jerry Burris' column appears Wednesdays in this space. See his blog at blogs.honoluluadvertiser.com/akamaipolitics. Reach him at jrryburris@yahoo.com.