Washington, July 7: Perhaps for the first time in his life, Barack Obama may have reason to commiserate with the likes of Bill O’Reilly, Rush Limbaugh and George Allen. They surely could tell him a few stories about what it is like when Mike Stark has you in his sights.

Stark, a 39-year-old former computer programmer and third-year law student at the University of Virginia, made a name for himself through his uncanny ability to get past the screeners for O’Reilly and Limbaugh and other right-wing radio hosts to ask embarrassing questions. He recorded the conversations and posted them on his website, and his renown grew.

Stark’s latest project has taken him to the website of Obama, who happens to be Stark’s choice for president. And while he said he did not relish making Obama a target, Stark is using the candidate’s own social-networking portal, my.barackobama.com, to confront him.

A little more than a week ago, Stark suggested to a group of liberal activists who share an e-mail list that they should organise a group on the portal to lobby their candidate to oppose legislation granting legal immunity to telecommunications companies that cooperated with the Bush administration’s program of wiretapping without warrants. The immunity is part of an update of the Foreign Intelligence Surveillance Act, or FISA, that is set to be debated this week.

“Obama is getting mad props for social networking,” Stark recalled arguing. “Why don’t we use social networking to let him know that he can’t keep elbowing his progressive base—the people who got him the nominatiom—away from the policy table?”

A member of my.barackobama .com started the anti-FISA group, and Stark quickly signed on.

In those 10 days or so, the group, with its ever-so-polite name, “Senator Obama Please Vote NO on Telecom Immunty—Get FISA Right”, has grown to more than 18,000 members and become the largest public group on the campaign site.

On Thursday, the movement drew a response from the candidate himself—a long, conciliatory note that explained his decision to support the FISA bill. “This was not an easy call for me,” Obama said in the statement, which was posted to the diary of Joe Rospars, a top Internet adviser to the campaign. “I know that the FISA bill that passed the House is far from perfect.”

The debate on Obama’s website shows how a force he has harnessed—the power of social networking—can also be an unruly, unpredictable one that can turn back on him.