On national security, events could take over and put the issue center stage. But McCain must lay the groundwork to take advantage of whatever situation develops. He needs to hammer home the accusation that Obama is "naive" and "inexperienced" - both of which are obviously true. He should run ads mocking Obama's claim that Iran is a "tiny nation" that could pose no real threat to the United States. He needs to hit hard at Obama's plans for Iraq and Afghanistan, hammer at Obama's opposition to the surge and refusal to vote to pay for the troops.

The offshore-drilling issue helps McCain, but it doesn't conjure the kind of fear that national security and the economy do. McCain has a long task ahead of him of burying Obama's credibility on these issues, and he needs to begin right away.

For better or worse, this election is about Obama. It is a referendum on the Democratic candidate and his agenda of change. McCain is a well-known commodity: Voter opinions of him are not likely to change much in the next three months. But their view of Obama is subject to wild fluctuation.

That's why the undecided vote right now is running at twice its 2004 percentage at this time in the race. That's why older women are withholding their approval of Obama. McCain can and must use August to tilt these doubts into negatives.

It's starting to look like McCain can win - if he does the right things.