There's a song in the musical "Evita" that labels politics "the art of the possible."

And thanks to politics, those possibilities are endless for the Capitol Steps, the Washington, D.C.-based comedy troupe that has been lampooning the nation's leadership since Ronald Reagan held office.

The bad boys (and girls) of the Beltway will roast the sacred cows of Washington this Thursday at Mount Gretna Playhouse. And nowadays, there's plenty of meat for the spit.

"Isn't it wonderful for our business?" quipped Mark Eaton, who's been performing with the political comedy gang since 1993.

There's the immigration debate swirling around the Mexican border; the ever-cool demeanor of President Barack Obama; and the British Petroleum oil spill in the Gulf of Mexico, which has provided plenty of comic fodder. Some "greasy fish," as Eaton put it, cavort in a number inspired by the Disney film "The Little Mermaid," and former BP Chairman Tony Hayward, who enjoyed a yacht race during the crisis, is an obvious target.

It's all in a day's work for the Capitol Steps, which came together in 1981. They started as a group of Senate staffers who literally decided to bite the hand that fed them and make fun of their employers. Three decades and 30 albums later, not all of the Steps have political pasts, but they're right on top of all things Washington.

The George W. Bush era got its due with Capitol Steps albums including "When Bush Comes to Shove" and "Papa's Got a Brand New Baghdad," and Obama's first term hasn't been spared. The Steps' 2008 effort "Liberal Shop of Horrors" features numbers such as "Strangers on This Flight" (a riff on the underwear bomber set to Frank Sinatra's "Strangers in the Night") and "Battle Hymn of the Tea Public."

The troupe strives to be equal-opportunity offenders, but even in the best of times, jokes don't always come easy. Asked if any administration figure has ever stumped the Steps, Eaton cited Barack Obama.

Obama, dubbed "No Drama Obama" by the group, doesn't possess Bush's peculiarities of language or Bill Clinton's way with the ladies. ("We love a good sex scandal," he said.)

"Thank goodness for people like Joe Biden," Eaton said of the gaffe-prone vice president. Still he, lamented, "Will anything be as funny as Dan Quayle, Clinton or Bush?"

Not to worry. There are plenty of others, like Sarah Palin, "the hottest former governor from the coldest state," as Eaton referred to the half-term Alaska leader, one-time vice presidential candidate and permanent presence on the political scene.

In fact, all of Congress is in the cross hairs — especially a Congress that promised to be "the most ethical … in history." Easton laughed. "Drain the swamp, and there's Charlie Rangel's vacation house."

Though immigration is at the forefront of the national debate, Eaton said controversial Arizona Gov. Jan Brewer, who favors tough crackdowns on illegals, isn't really on the Steps' radar. She's just not as well-known a state leader as Palin or California's Arnold Schwarzenegger, Eaton said.

Though they hail from Washington, the Steps have to be careful not to be too insider-minded. While 10 people inside the Beltway might think a certain item is important, issues that have the capital abuzz can draw yawns from the rest of America.

"You've always got to feel your way," Eaton said.

Even perceived sure things don't always pan out. Former Republican Sen. Larry Craig's toe-tapping antics in an airport men's room, where he allegedly tried to pick up an undercover police officer, generated tons of material back in 2007. But Eric Massa, the Democratic congressman who resigned this year amid allegations he groped male staffers and admitted engaging in a "tickle fight" with male aides, didn't fly.

"The tickle fight got almost nothing," Eaton said.

Still, as long as Washington stands, hope springs eternal for the Capitol Steps. Asked about the upcoming election season, Eaton said he hopes things get down and dirty.

"Our greatest enemy is competence in government," he said. Then again, "we're not in danger of going out of business."

The Capitol Steps appear at 8 p.m. Thursday, Aug. 26, at Mount Gretna Playhouse. Call the box office, 964-3627 or log on to gretnamusic.org.