Twelve months, hundreds of millions of dollars spent, major news stories such as jobs reports and the Supreme Court’s health-care decision, and, according to this morning’s Washington Post poll, the race for the presidency remains stuck in a tie.

There are hopeful tea leaves in the poll for both sides — President Obama’s negative ads on Bain seem to be cutting a bit in swing states — and Mitt Romney can take comfort in a political atmosphere that continues to be extremely hostile to the incumbent. But this race in July is unusual; it already resembles what many presidential races look like in October: the bases firmly entrenched for both candidates with a very small percentage of undecided voters. These poor souls are increasingly punch-drunk from all the ads and voter contact aimed their way. One interesting follow-up on the Post poll might be to analyze the demographics and attitudes of these undecideds. My guess is this group would show a propensity to break for Romney. Most incumbents, facing the kind of headwinds prevalent today, don’t catch the break.

So if the race is already in lockdown, what might influence it between now and November? On the macro-level, of course, there could be major economic or international events that could swing the race. A gross simplification holds that the former benefits Romney, while the latter helps Obama. But, on a more predictable level, as The Post notes, the mechanics of the campaign could be determinative in a close election.

On voter contact and turnout, as I have pointed out, the Obama campaign has a huge advantage. It has an infrastructure built and improved over the past five years, and it is investing millions in micro-targeting and message delivery. For example, my online version of The Post’s article on the presidential poll was surrounded by Obama ads attacking Romney’s supposed job outsourcing. That’s thoughtful ad placement, and small decisions like that made every day can tip a race ever so slightly. In 2008, Obama’s campaign had the uber-message of hope and change; today, it has a bank of servers cranking out lots of small, customized messages to slivers of audiences that it hopes add up to victory.