TUESDAY'S PRIMARY, which promised to be a stand-your-ground gig for Rick Santorum, is now an election without any pop.

Once Rick disengaged, the body politic sagged, shrugged and surrendered.

Yes, Rick, Mitt, Newt and Ron Paul — three with Pennsylvania ties — all are on the ballot. But, come on, it's over for the GOP. And, for Democrats, the president's unopposed so the energy of '08 is but a distant memory.

This means no statewide interest, low voter turnout and zero animation in all but a couple of races.

Even if voters are angry and vengeful over gas prices, stupid legislators or a still-stunted economy, they must feel primary voting just won't change a thing.

In many ways they're right. Take congressional races.

Philly and its 'burbs have no action: Bob Brady, Chaka Fattah, Allyson Schwartz, Mike Fitzpatrick and Pat Meehan all are unopposed.

In the Legislature, although city seats are contested, only a few generate interest: veteran incumbents Angel Cruz, Jim Roebuck, Babette Josephs and Mark Cohen face organized opponents.

Statewide, 203 House and 25 Senate seats are up (only half the Senate runs in even-numbered years). Forty percent have no opposition.

If voters are filled with disgust and distrust, why are officeholders unchallenged?

Why doesn't tea-party anger or "occupy" protest translate into vigor for voting?

It's like problems are unfixable, hope is dead, so let's hold a zombie primary.

"Disinterest," says T. J. Rooney, a former Democratic state party chairman who's now a consultant in Bethlehem and who agrees that few folks are paying attention.

He says party endorsements, labor endorsements and even individual endorsements don't spark energy or carry the weight they once did.

"Social media allows folks to get more access to information and they then can make up their own minds," Rooney says.

I'd add that trust in normal networks, whether parties, unions or current/former officeholders, is greatly diminished.

Take the tight Democratic race for state attorney general.

Former Bucks County U.S. Rep. Patrick Murphy, by every measure of primary politics, should be a walk-away winner.

He's an Army veteran with an impressive resume. He has endorsements from unions, advocacy and special-interest groups, endorsements from state and local political figures and he lives in a media market with a-third of the state's Democrats.

But his opponent, former Lackawanna County prosecutor Kathleen Kane, is a qualified first-time woman candidate at a time of national noise about gender gaps, in a state notorious for too few women in public office.

If she wins, it would be considered an upset, and yet it would not be a surprise.

Lack of interest/low-turnout in Philly could hurt Murphy. And Kane is expected to do well in other media markets.

Lack of interest affects another race, too.

When I ask Charlie Gerow, a Harrisburg-based Republican consultant and analyst, about interest on the GOP side, he says, "It's underwhelming. You have a U.S. Senate primary that's getting almost no attention."

The five-way race to oppose Sen. Bob Casey is narrowed to a fight among three. The party-endorsed candidate is 35-year-old Bucks County entrepreneur Steve Welch; the western candidate, former coal-company owner Tom Smith, of Armstrong County, is outspending Welch 3-to-1; and the grass-roots candidate, former state Rep. Sam Rohrer, of Berks County, got 31 percent of the vote in the 2010 primary for governor by running to the right of Tom Corbett.

Had Santorum stayed, Rohrer would have gained from the conservative base.

As it is, the contest is party backing versus money versus regionalism.

Western counties vote in higher proportion than eastern counties and are known for loyalty to locals; on primary ballots, county residence is listed with candidates.

So, as in all elections, outcomes will be determined by levels of turnout in each region — even as this election draws a statewide yawn. n

For recent columns, go to philly.com/JohnBaer. Read his blog at philly.com/BaerGrowls.