Not every politician gets a week like the one John McCain got last week, and most of his good fortune was not of his making. Yes, he did clear the threshold of 1191 delegates to officially gain the nomination and, yes, that did lead to a helpful photo-op at the White House. But the real gifts were delivered by his potential Democratic rivals and by the Democratic Party itself.

Most obviously, Hillary Clinton did not quietly exit the stage. By beating Obama badly in Ohio, she ensured the race would go on and the intra-party warfare would continue. Her victories revealed Obama’s weakness in attracting lower income whites and Hispanics, two groups he would need to hold in November.

Barack Obama also lent credence to Clinton’s point that maybe foreign policy leadership does require experience when his advisers were caught assuring foreigners that their boss does not really mean all that wacky stuff about reneging on NAFTA and bugging out of Iraq when things are improving.

Obama’s efforts to shoo away the offenders did not settle the underlying dilemma — is he being disingenuous with voters or does he not have command over his advisers? Suddenly there did seem to be a stature gap between him and Clinton, who can at least keep her advisers from publicly undermining her policy pronouncements.

McCain got the soundbite equivalent of “I voted for the $87 million before I voted against it” when Obama adviser Susan Rice said of the Democratic contenders, “They’re both not ready to have that 3 a.m. phone call.” Clinton pitched in as well, repeatedly saying that both she and McCain have a lifetime of experience but Obama…maybe not so much.

These events reinforced the reason for McCain’s candidacy: he is unmatched in foreign policy acumen and experience. Clinton will make half the argument on a daily basis, lambasting Obama as a neophyte. Obama will make the other half, pointing out that Clinton is scarcely better prepared. Meanwhile, McCain will be jetting to foreign countries, meeting with foreign leaders and proving his point that he is the only one ready for national security responsibility.

And last week’s attack on the military recruiting station in New York City and the terrorist shootings in Jerusalem served as reminders, if any were needed, that we live in dangerous times.

HOWARD DEAN AND the Democratic Party did their part as well. The problem: Michigan and Florida. Their solution: They have not a clue.

The prospect of redo primaries or an ongoing rules fight over whether to exclude the delegates gives Clinton more reason to soldier on. The possibility that no arrangement can be found and that two of the most populous states will have no say in selecting the Democratic nominee raises the delicious prospect that a Democratic nomination arrived at without allowing every vote to be counted. It would reek of unfairness and send many voters (at least in Florida) running into McCain’s open arms in November.

While all of this was going on, the Democrats and the DNC found it impossible to turn their guns on McCain, who is financially and organizationally at his most vulnerable. As Bob Dole found out in 1996, an underfunded Republican in the post-nomination and pre-convention period can collapse under attacks from a well organized and funded opposition. But the Democrats have too much on their hands to bother much with McCain, a situation that may go on for weeks or even months.

Now, many have speculated that McCain has benefited from one of the longest streaks of good luck in history. Mike Huckabee rose just in time to topple Mitt Romney. Rudy Giuliani left New Hampshire and virtually evacuated the race, leaving the early primary states to McCain. The surge worked in time for primary voters to appreciate McCain’s role in its success.

What politician has been this fortunate? The Democrats are starting to worry that McCain’s luck has only just begun.