A much-anticipated series of hearings on immigration enforcement kicks off Tuesday, but the hearings aren’t about a specific piece of legislation, exactly. And that’s no accident.

Instead, the hearings reflect a careful attempt by House Speaker Nancy Pelosi, D-Calif., to maintain some semblance of control and keep the peace with two crucial constituencies — “Blue Dog” Democrats interested in get-tough immigration legislation and Hispanic Caucus members who don’t want to see anything short of legislation that includes a path to citizenship for illegal immigrants.

Based on the rhetoric thus far, Pelosi’s efforts at compromise have proved less than successful. But given the emotion and divisiveness of the immigration issue, harmony, even among Democrats, may be too much to hope for.

What has forced Pelosi’s hand is an enforcement-oriented bill (HR 4088) introduced last fall by Heath Shuler, D-N.C., a freshman from a conservative district previously held by the GOP. Shuler’s bill would authorize the hiring of 8,000 additional border agents and create a mandatory system for verifying the legal status of workers and job applicants.

Conservative Blue Dog Democrats, some of them vulnerable freshmen like Shuler, prefer the get-tough approach in his bill. But what really got Pelosi’s attention was a discharge petition filed on the bill by GOP leaders. It has drawn 187 signatures, including those of 10 Democrats. Momentum toward the 218 signatures necessary to carry the petition has slowed almost to a halt in recent weeks, but if successful, a discharge petition would let the bill “leapfrog” normal order and go directly to the House floor. In early April, after a 90-minute meeting with several key committee chairmen, among others, Pelosi agreed to hold hearings. But as it turns out, those hearings will be only loosely based on the provisions of Shuler’s bill.

Shuler will appear at one of Tuesday’s sessions, before the Social Security Subcommittee of the House Ways and Means Committee. That panel will be looking at various employment verification systems including E-Verify, an Internet-based government system that employers can use to check employees’ work eligibility by verifying Social Security numbers. The system is presently voluntary everywhere but Arizona, where a state law requires it. Shuler’s bill would mandate use of E-Verify nationwide, but critics fear glitches in the system would interfere with the delivery of Social Security benefits.

“We had always hoped that the bill would go through regular order,” said Andrew Whalen, a spokesman for Shuler. “While [the hearing is] not a markup . . . it’s a step in the right direction.”

In the other hearing Tuesday, before the House Education and Labor Committee, lawmakers will examine whether U.S. workers are being actively recruited for some open jobs before employers look overseas.

Also planned are hearings on border security, before the Homeland Security Committee, and hearings on employment verification systems and Immigration and Customs Enforcement raids, before the Judiciary panel’s Immigration and Citizenship Subcommittee.

Firm dates have not been set, but it is hoped those hearings will be held before the Memorial Day recess.

Pelosi may have put the ball in motion by ordering the hearings on enforcement, but since then, it has been up to the committees to claim their piece of the immigration puzzle. Coordination between panels has been lacking — evidenced by the competing panels Tuesday — though some suspect the resulting inefficiencies may be part of the overall plan.

Pelosi, a longtime supporter of comprehensive legislation that might include guest worker programs and a path to citizenship, is unlikely to push forward any sort of sweeping measure this year.

Pelosi is “walking the narrowest of tightropes, with pressure coming from all sides on a high-profile issue,” said Angela Kelley, director of the Immigration Policy Center at the American Immigration Law Foundation. The hearings are, in effect, a means of ratcheting down public bickering over the issue and putting it on ice until at least next year, Kelley said: “We’re just buying ourselves a short-term break from the issue . . . so we’re going to be seeing more speeches than substance.”

But fiery rhetoric is expected.

“There’s an agenda out there to not take any action on this item until after the election, which indicates to me [the Democrats] don’t want the American people to know where they are on this issue,” said Rep. Brian P. Bilbray, R-Calif., chairman of the Immigration Reform Caucus, which promotes an enforcement-oriented approach.

Members of the Congressional Hispanic Caucus, meanwhile, say they feel abandoned. At a late-April news conference, Raúl M. Grijalva, D-Ariz., called the Democratic Caucus “spineless” and said the Shuler bill was “an attempt to be más macho than Tom Tancredo,” referring to the Colorado Republican who has led the tough-on-illegal-immigration faction in the House.

Rep. Luis V. Gutierrez, D-Ill., echoed those thoughts more recently.

“I will not vote for nor support an enforcement­-only, piecemeal measure which throws a few crumbs to the most vulnerable among us,” he said last week.

Other, more narrowly targeted proposals, like increases in visas for seasonal workers or educated, high-tech workers, have failed to come to the floor through either committee markups or discharge petitions. Measured by legislative success, not much is happening. But the noise level is quite high.

“It’s . . . a rather bleak situation,” said Frank Sharry, director of America’s Voice, an immigrant-advocate group. “House leadership thought this issue might go away until after the election . . . but immigration policy abhors a vacuum.”