WASHINGTON » Rep. Pete Sessions, R-Texas, is no stranger to town hall meetings and their political possibilities. Four summers ago, he helped his party use them to stoke opposition to President Barack Obama’s proposed health care overhaul. Across the country, forums like his fed a budding Tea Party movement and set the stage for returning the House to Republican control in 2010.

But when Sessions returned to his Dallas-area district for the August recess this year, a pause before Congress takes up an agenda that includes immigration, government surveillance, health care and budget cuts, there was something conspicuously missing from his schedule: a town hall.

One of his constituents, Katrina Pierson, 37, who describes herself as a "conservative grass-roots volunteer" and had hoped to press Sessions on his commitment to pulling financing from the health care law, is so exasperated that she and a group of like-minded advocates have offered to host a meeting for him. "He can just give us a date," she said. "We’ll set it up."

Though Republicans in recent years have harnessed the political power of these open-mike, face-the-music sessions, people from both parties say they are noticing a decline in the number of meetings this time around. They also say they are seeing congressional offices go to greater lengths to conceal when the meetings take place and where they will be held.

"The whole thing is very anti-democratic, and it’s classic behavior of entrenched insiders," said Matt Kibbe, the president of FreedomWorks, a Tea Party group that in 2009 helped send legions of demonstrators to the sessions. Now it is trying to draw out seemingly reluctant members by staging public events like mock town halls with empty chairs. "We’ve lost that Rockwell image of citizen participation in democracy."

With memories of those angry protests still vivid, it seems that one of the unintended consequences of a movement that thrived on such open, often confrontational interactions with lawmakers is that there are fewer members of Congress now willing to face their constituents.

Members of Congress and their aides were reluctant to talk about the lack of town halls on the record, mindful of the pressure from liberal and conservative groups alike. "Ninety percent of the audience will be there interested in what you have to say," one Senate Republican aide said. "It’s the other 5 or 10 percent who aren’t. They’re there to make a point and, frankly, to hijack the meeting."

Indeed, many who attend the meetings now seem intent on replicating clashes like one from Pennsylvania in 2009, when former Sen. Arlen Specter, a Republican turned Democrat, was shouted down by an angry constituent, a scene captured on camera and played on an endless loop on cable news.

"The reason 2009 was so successful for the grass-roots was because the politicians never saw it coming," said Jennifer Stefano, the state director for the Pennsylvania chapter of Americans for Prosperity, a Tea Party group. "Now they know. And they are terrified."

Many lawmakers, often from safe districts, are still holding town halls throughout the month. While a number of them are drawing voters outraged over Obama’s health care law, the intensity is nothing compared to the scale of 2009.

But where there are no gatherings, some groups have decided to take matters into their own hands.

After seeing a paltry schedule of congressional town hall meetings this month, another major conservative group, Heritage Action for America, decided it would stage public forums of its own from Arkansas to Pennsylvania. The aim is to recruit people for a group it calls the Sentinels, a citizens’ brigade of sorts to reach lawmakers through other means, like writing letters to the editor, dialing in to talk-radio programs and mastering the language of Twitter and Facebook.

The Democratic Congressional Campaign Committee is sending its advocates into Republican districts with two-dimensional cutouts of members without a traditional town hall on the calendar. Anyone who is feeling especially theatric is being encouraged to debate their cardboard congressman.

This month, the committee sent a batch of rubber ducks to Rep. Rodney Davis, R-Ill., who is under pressure to support a broad immigration overhaul. (The joke: He is "ducking" questions in an ethics investigation.) Others on the Democrats’ target list have included Rep. Tim Griffin, R-Ark., who was greeted at an airport by protesters calling for an end to the across-the-board budget cuts known as sequestration, and Rep. John Kline, R-Minn., who is also being pressed to support immigration overhaul and was picketed after attending a closed-door Chamber of Commerce event. Not one of the Republican congressmen has a town hall on scheduled this month.

Pierson and Tea Party advocates from around Dallas spent one night last week making fake milk cartons with pictures of Sessions and Sen. John Cornyn, another Texas Republican who has yet to announce a town hall.

Absent Cornyn or Sessions, Pierson said she and her friends would hold their own meetings, complete with YouTube clips of the two talking about charged issues like border patrols and National Security Agency data sweeps. There is even discussion of a "Saturday Night Live"-style impersonator of Sessions, a member who is in high demand because of his powerful job as chairman of the House Rules Committee.

A spokeswoman for Sessions said he had no town halls on his schedule this month, but she noted that he regularly engaged with constituents, whether in public meetings he held this year or by giving out his personal email address to anyone who asked. Cornyn’s office said it was still working out his schedule for the month.

Most of the efforts to publicly shame members of Congress who are not scheduling town halls are aimed at Republicans. Tea Party groups are focused mainly on pressuring fellow Republicans — not Democrats, who would largely be a lost cause — to get behind a proposal to shut down the government if financing is not pulled from the president’s health care law.

Immigration groups, like Alliance for Citizenship, which supports a plan like the Senate’s that would grant citizenship to the 11 million people here illegally, are almost exclusively targeting House Republicans, who now hold the key to passing any immigration overhaul legislation. The Democratic-controlled Senate has already approved one. One of the alliance’s targets this month has been Rep. Eric Cantor, the House majority leader, who has not announced any town halls but did participate in them in 2009.

Even if more lawmakers schedule public meetings – and many still might, with four weeks left in the recess – they would not always be easy to find or get into. Republican and Democratic advocates said congressional offices have gotten increasingly clever about keeping their schedules under wraps.

Sometimes, they wait until the last-minute to announce the meeting, advocates said. Other times, they book a room that cannot accommodate large crowds and then alert their supporters to arrive an hour early so that the audience fills up with friendly faces. Many now prefer to hold forums over the phone, a format that allows an operator to screen callers and minimizes the chance for the kind of disruptions that could be recorded and distributed by camera-wielding campaigners.

"To quote Lindsey Graham, if you have nothing to hide, you have nothing to be afraid of," said Kibbe of FreedomWorks, paraphrasing comments by Sen. Graham, R-S.C., defending NSA data collection.

The first name on FreedomWorks’ website DemandATownHall.com is Graham’s. The senator currently has no town halls scheduled this month.

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