Pick your metaphor for the impossible job Republican House Speaker John Boehner has faced for the last five years: Sisyphus, Dutch boy with his finger in the dike, cat-herder-in-chief. You get the idea.

Even worse, he had no influence over a large segment of the cats: the fire-eating conservative representatives elected in the tea party wave of 2010 that gave the GOP the majority in the House but were immune from the normal rewards and punishments of legislative politics.

Conservative lawmakers and activists, who have long blamed Boehner for capitulating to Democrats, celebrated his departure and predicted that their House conference would now push further right and adopt an even more confrontational stance.

"This is a victory for the American people," said Rep. Tim Huelskamp (R., Kan.), one of the speaker's more fervent detractors. "We need a speaker who actually has lived and can articulate the conservative principles of the Republican Party."

For the moment, the Ohio Republican's sudden announcement he would leave office at the end of October will avert a government shutdown, as Boehner is now free to move a spending bill without the provision stripping federal funding from Planned Parenthood pushed by the more conservative members of the caucus.

Democrats can put up votes for the spending bill with Boehner no longer having to watch his back.

In the longer run, the tensions splitting the House Republican caucus are unlikely to abate.

For his part, Boehner, 65, said he had long planned to quit by year's end but wanted to spare colleagues the turmoil that has come to surround his speakership. Conservatives in the House have been pushing for a vote to oust him, and speculation on his future has become a Washington parlor game.

"There was never any doubt about whether I could survive a vote," he said at a news conference. "I do not want my members to go through this, and I certainly don't want the institution to go through this, especially when I knew I was thinking about walking out."

Jocular and emotional, he displayed both qualities Friday. "OK, junior, go ahead," he said, calling on one reporter. He teared up - as he so often does - while talking about a private moment with Pope Francis.

Boehner owed his ascension to the hard-line conservatives who swelled the GOP's ranks, but he is a classic deal-maker and struggled to strike a balance between the need to compromise in order to govern and the more purist ambitions of the newer conservatives in the House.

The prospect that the caucus may now veer right worried Philadelphia-area Republicans, who represent moderate districts and have often chafed at the brinkmanship of colleagues from redder states.

After all, they said, the forces that stymied Boehner will face a new speaker: a Democratic president and a Senate where bills need 60 votes, requiring bipartisan support.

"To lead a diverse conference like the Republican conference, you have to have somebody that's going to be pragmatic, that's going to realize that there are Democrats who vote in here," said Rep. Tom MacArthur (R., N.J.). "There are conservatives and there are more moderate members, and if you don't get the requisite number of votes, you don't move forward anything."

He and other GOP House members from the Philadelphia area have pushed against that strategy. Rep. Ryan Costello of Chester County has circulated a letter among fellow GOP freshmen opposing a shutdown. Passing bills will still require cooperation with the president, said Rep. Pat Meehan (R., Pa.).

"None of those dynamics change by John Boehner's stepping down," Meehan said Friday. "We've got to act responsibly here, demonstrate that we can do the best we can, and make the case for a Republican president in the next cycle."

Rep. Charlie Dent of the Lehigh Valley said some of his fellow Republicans "wanted to take down the speaker."

"They never had a horse of their own," Dent said. "Any jackass can kick down a barn door - it takes a carpenter to hang one. We need a few more carpenters around here."

In order to muster bipartisan support for a series of critical bills, Dent said, "The next speaker has to be willing to say, 'If you're not willing to govern, we will make you marginal and irrelevant, and we will find those who will help us.' "

At the same time, some on the right, and much of the party's base, have fumed over congressional Republicans' inability to pass purely conservative bills or block more of President Obama's initiatives, despite holding both the House and Senate. That anger is in large part driving the race for the GOP presidential nomination.

The activists ask: We have the majority, and what are we doing with it?

One candidate, Sen. Marco Rubio (R., Fla.), broke the Boehner news to a cheering crowd at the Value Voters Summit in Washington, a gathering of social conservatives.

"The time has come to turn the page," Rubio said as the audience erupted. "That extends to the White House and the presidency as well."

Even the relatively moderate Gov. Christie of New Jersey has taken to bashing the GOP-run Congress for not living up to campaign promises such as repealing and replacing Obamacare. "This is why people can't stand Congress," Christie said on Meet the Press last week.

"Americans deserve a Congress that fights for opportunity for all and favoritism to none," said Michael A. Needham, who heads a policy arm of the conservative Heritage Foundation, in a statement. "Too often, Speaker Boehner has stood in the way."

Failure of the effort to push removing federal money from Planned Parenthood, in protest of the organization's selling of fetal tissue from abortions for medical research, could inflame the GOP base even more, analysts said.

"This is a moment where candidates need to watch the tone," said Craig Robinson, editor of the Iowa Republican website and former political director of the Iowa GOP. "There's going to be some anger, real visible anger, with conservative Republicans" if the GOP doesn't push for a shutdown over Planned Parenthood.

"But if you're Ted Cruz, that plays to your base," Robinson said. "Then again, it also pushes you more to the extreme of the party." That could endanger the eventual GOP nominee's general-election prospects, he said.

Boehner's exit "plays well with conservative activists who like to listen to talk radio and cable news," Robinson said. "I think the unfortunate part of this - it lacks the kind of the governing reality that's out there."

He added, "I feel for whoever follows Boehner. Good luck. I don't know if you'll ever satisfy the talk-radio, cable-news caucus."

How to assess Boehner's reign? One congressional scholar used terms reminiscent of Shakespearean tragedies - a leader outflanked by his foes, undercut by his friends.

He was "outmaneuvered" by Obama in seeking a so-called grand bargain on fiscal policy, "undercut by his own caucus, and constantly shadowed" by then-House Majority Leader Eric Cantor of Virginia, said Ross K. Baker of Rutgers University.

Baker said as many as 40 House Republicans had no interest in compromising with Democrats, and Boehner struggled to either placate or discipline the troublemakers.

"He never had a moment's peace," Baker said. "It's just no way to live. He'd much rather go out and play golf."

215-854-2718@tomfitzgerald