Nothing like a politician's final, pre-election TV ad to tell you what he or she wants voters to remember when they go to the polls. And as if on cue, both Barack Obama and Hillary Clinton released new spots this afternoon (only hours before voting begins in North Carolina and Indiana) that neatly sum up their homestretch strategies--and reveal their greatest weaknesses as candidates.

Clinton first. Her clip is called "What's Happened":

The New York senator is hoping, of course, that voters view her as the candidate "who's going to keep fighting for working people"--while superdelegates ask the question, "What's happened to Barack Obama?", that opens her ad. For the past week, Clinton has been largely content to push her gas-tax proposal--a preposterous political pander that economists say will actually raise prices at the pump--as a way of conveying her blue-collar cred. But now she's going one step further, claiming that Obama "is attacking Hillary's plan to give you a break on gas prices because he doesn't have one." The problem: it's not true. In fact, Obama wants to accelerate the second half of his tax-stimulus proposal to "put, immediately, hundreds of dollars into people's pockets to get through the summer" and "pass a permanent middle-class tax cut, $1,000 per family, to offset the payroll tax to deal not just with rising costs of gas, but also rising costs of food, rising costs of prescription drugs." In other words, Clinton is all to eager to go negative--even when the facts aren't in her favor. Anything to win, indeed.

Now Obama. Here's his new spot, called "Hometown."

Obama's point? To attack Clinton for attacking him--and portray her as part of "the same old Washington politics" that "won't fix our problems." To make the case, Obama cites a recent editorial in the New York Times ("her hometown newspaper") that "says she's taking the low road" and that "her attacks do nothing but harm." It's a sly move; in effect, Obama is letting a newspaper throw his punches for him. But "Hometown"--which, after all, implies that Clinton isn't "honest" and can't be "trust[ed]"--is a negative ad all the same, and will likely expose Obama to some charges of last-minute hypocrisy. Still, that's not the problem. Obama was right to swing back; the more pugilistic he seems at this point--especially to superdelegates--the better. It's the fact that he didn't say anything of substance that bothers me. Instead of refuting Clinton's "he doesn't have a plan" canard with a quick, informative summary of his relief proposals, Obama is content to make yet another process argument against "politics as usual." It's the difference between showing us how Clinton is dissembling and merely telling us that she is. And ultimately the spot ends up sounding like a platitude--which is exactly the perception that's been killing Obama among downscale Dems in state after state.

Same old dogs, same old tricks.

UPDATE, 8:00 p.m.: Breaking! (Or not really breaking at all.) An earlier Obama ad, called "Pennies," actually countered Clinton with substance, mentioning Obama's plan to "give working families a permanent, thousand-dollar tax cut to help with rising costs." But that wouldn't come into effect until Jan. 2009. So we deduct half of Obama's demerits, but still fault him for choosing to talk about process instead of saying how he would help consumers get through the summer (i.e., by accelerating the second half of his tax stimulus proposal.) Anyway, here's the spot: