There’s a school of thought that says presidential campaigns shouldn’t go on the offensive too early. The election season is a marathon, the argument goes, and campaigns that do too much, long before the electorate is fully engaged, risk running low on resources when crunch time hits in the fall.

Hillary Clinton’s campaign has no use for these assumptions. NBC News reported yesterday that the Democrat’s “first battleground advertising blitz of the general election” has begun.

uses the TV ad it unveiled on Sunday hitting Trump (“What kind of America do we want to be? Dangerously divided or strong and united?”), as well as two new positive bio spots on Clinton ( here and ). […] The TV ad buy – in Colorado, Florida, Iowa, Nevada, New Hampshire, North Carolina, Ohio, and Virginia – has a price tag of at least $7.3 million. And it here ). […] More than anything else, the ad blitz demonstrates Clinton’s financial superiority right now. How long will she have the battleground-state airwaves to herself? Remember, the pro-Clinton Super PAC is already on the air in these states. But where’s the Trump/GOP cavalry?

The answer, of course, is that this cavalry doesn’t exist. On the contrary, as we discussed last week, Trump is falling behind financially – and disputes the idea that he’ll need to catch up.

But what about the long-held assumptions about campaigns wasting money by going on the air too early? Team Clinton doesn’t buy it, and they have some recent evidence to back up their plans.

The New Republic noted overnight that President Obama’s re-election campaign hit the airwaves aggressively in May and June, making a concerted effort to help define Mitt Romney early on. It was money well spent: by the time the “47 percent” video hit, “the narrative that destroyed Romney’s candidacy was already in place.”

Four years later, the circumstances aren’t identical, but Team Obama helped show that early ad buys are seen, can have an impact, and help set the stage for what’s to come.