What more will Congress do or say about the recent disclosures about top-secret National Security Agency programs that can track telephone calls and Internet searches? It's a subject that promises to dominate the week -- especially now that a 29-year old former NSA contractor has come forward as the source of the embarrassing leaks.

National Security Agency (NSA) headquarters at Fort Meade, Maryland, as seen from the air, in this January 29, 2010 file photo. (Saul Loeb/AFP Getty)

Debate on the NSA's years-long effort to compile telephone records and to track Internet searches through its PRISM program appears to be breaking along predictable fault lines. First, there are defenders of the programs, then the longtime critics, and then lawmakers upset they didn't know or who want more information.

Senate Intelligence Committee Chairman Dianne Feinstein (D-Calif.) and House Intelligence Committee Chairman Mike Rogers (R-Mich.), who are involved in authorizing and overseeing the programs, clearly fall into the first group. On Sunday, Feinstein said that the recently revealed surveillance programs have thwarted two major terrorist plots in New York and Mumbai. And Rogers once again defended the program, saying that the NSA doesn't listen in on telephone calls or read Americans' e-mails.

The program's chief critics, Sens. Ron Wyden (D-Ore.) and Mark Udall (D-Colo.), sit on the Intelligence Committee but have been raising concerns for years. Udall conceded Sunday that PRISM has helped yield helpful information, but said he doesn't understand why the NSA continues to track so much phone data in a separate program if it hasn't helped thwart an attack.

Then others in the House and Senate, including Sen. Barbara A. Mikulski (D-Md.), say they want top national security officials to share more information with lawmakers about the program. But in the wake of the reports, Feinstein, Rogers and senior Obama administration officials have said that lawmakers have had several opportunities to learn more about the programs in recent years.

This much we know: Lawmakers surely will want to learn much more about Edward Snowden and how a young contractor based at an NSA facility in Hawaii -- who never even earned a high school diploma -- was able to access some of the most sensitive documents available to members of the intelligence community.

What's the Senate doing this week?

Debate on a bipartisan immigration reform bill is scheduled to begin in earnest this week after months of anticipation. Supporters of the proposed immigration overhaul earned key support Sunday from Sen. Kelly Ayotte (R-N.H.), who called the bill a "thoughtful bipartisan solution to a tough problem."

Ayotte's support could prove critical, as supporters will need to secure at least 60 votes -- and hope to earn the vote of as many as 70 senators. Notably, Senate Majority Leader Harry M. Reid (D-Nev.) told Univision on Sunday that he expects to have just 90 percent of Senate Democrats -- not 100 percent -- meaning Republicans like Ayotte would need to make up the difference.

Reid also made clear in the interview that he will not permit votes on "poison pill" amendments designed to slow or all but upend attempts to change the nation's immigration laws. Reid called out a proposed amendment by Sen. John Cornyn (R-Tex.) that would require complete protection of the U.S.-Mexico border before any immigrant received permanent legal status or citizenship.

How Republicans react to Reid's comments could be critical to how quickly and easily the immigration debate proceeds in the Senate.

And how about the House?

The biggest piece of legislation on the House calendar this week is the expected consideration of the National Defense Authorization Act, which sets annual Pentagon policy. The bill includes several provisions that would change how the U.S. military tracks and prosecutes allegations of sexual assault in the ranks.

Among other bills, the House is also scheduled to vote on several land swap bills and legislation that would make changes to the Dodd-Frank financial regulatory reforms.

And House Speaker John A. Boehner (R-Ohio) is scheduled to lead Congress in paying tribute to Rep. John Dingell (D-Mich.), who last week became the longest-serving lawmaker in U.S. history. The ceremony will be held in the storied Statuary Hall at the U.S. Capitol on Thursday.

Also of note

1.) As of this writing, there are no hearings scheduled this week regarding the Internal Revenue Service, Justice Department or State Department, the three entities that have caused embarrassment for the Obama administration in recent months. On the IRS, Rep. Elijah Cummings (D-Md.), the ranking Democrat on the House Oversight and Government Reform Committee, said Sunday that the matter is effectively settled because an unnamed IRS manager essentially told committee investigators that it was he who started the targeting of the certain groups seeking tax-exempt status and that the White House wasn’t involved.

2.) New Jersey politics -- always rough and tumble -- begin a new chapter Monday because anyone interested in running for the U.S. Senate seat of the late Sen. Frank Lautenberg (D-N.J.) has to file by the end of the day. Reps. Frank Pallone (D-N.J.) and Rush Holt (D-N.J.) and Newark Mayor Cory A. Booker are candidates in the Aug. 13 Democratic primary. Steve Lonegan, the former head of the New Jersey chapter of the Koch brothers-affiliated Americans for Prosperity, is so far the only Republican to jump in. The special election for Lautenberg's remaining term is on Oct. 16.

Follow Ed O'Keefe on Twitter: @edatpost