D.C. is once again trying to jumpstart digital TV — and the biz, if not yet the consumer, is responding.

The Peacock, for example, broadcast the May 4 Kentucky Derby in hi-def, and will make a feed available to affils equipped to air a digital signal.

In fact, all the major nets are offering more and more hi-def programming. At first, it was mostly sports programming, with the Eye in particular serving as pioneer. Now, however, a surprising amount of primetime network programming is being aired in hi-def.

This sudden spurt in digital programming is no coincidence: May 1 was an official deadline for U.S. TV stations to begin offering a hi-def signal or other advanced service.

As of the deadline, some 314 of the country’s 1,309 commercial stations were offering a such a digital signal. Most of these stations are in large markets, including Los Angeles. (The top New York stations were ready to go until the 9/11 terrorist attacks brought down the digital antennae atop the World Trade Center towers.)

The National Assn. of Broadcasters says the 314 digital stations cover 85% of U.S. TV households. Smaller stations say it’s too expensive to make this transition.

Still, Capitol Hill lawmakers want to see more progress on the digital front.

The original bargain between broadcasters and pols made back in the mid-1990s was a simple exchange — Congress gave broadcasters a whopping $70 billion in free digital spectrum. In return the TV biz was supposed to offer hi-def programming, or other advanced services, such as interactive TV or video-on-demand — and do so May 1. In turn, broadcasters would return the analog airwaves they had occupied for decades.

Sen. John McCain (R-Ariz.) is an especially harsh critic of the TV biz’s subsequent hemming and hawing.

“I believe that broadcasters, as beneficiaries of this Great American Spectrum Rip-Off, bear heightened responsibility for facilitating the DTV transition,” McCain said in a statement marking the May 1 deadline.

The feisty pol said broadcasters should be forced to return the analog spectrum by Jan. 1, 2007, whether or not they are ready to go digital.

Technically, TV station owners don’t have to return the old airwaves, which are slated to be auctioned off by Washington to the wireless biz, until 85% of TV households have digital TV equipment.

That’s a tall order by any measure: Only a minuscule number of Americans own a TV set able to receive a digital signal.

Federal Communications Commission chair Michael Powell recently asked the various parties to share in the pain and begin persuading TV viewers that it’s time to make the digital switch.

Broadcasters, cablers and the consumer electronics biz have all embraced his voluntary plan.

But it’s going to take some work to persuade consumers: Digital TV sets cost anywhere from $1,000 to $3,500.

The major broadcast nets, as well as HBO and Showtime, have accepted Powell’s challenge to broadcast half their fall primetime lineup in hi-def. (Some are already doing so.)

And beginning Jan. 1, the country’s 10 top cablers have agreed to carry up to five digital broadcast and cable channels at no charge. The caveat: These channels must be offering 50% of their primetime programming in hi-def.

The consumer electronics industry has rallied to Powell’s call to begin equipping TV sets with digital tuners on a staggered basis, commencing Jan. 1, 2004.

Powell’s blueprint could actually result in real progress, although broadcasters still insist that the whole transition is useless until cablers agree to carry all digital signals — at no charge.