WASHINGTON (AP) -- Republican congressional leaders promise there will be no federal government shutdown this year. But with Congress, it's never easy.
A band of conservatives say they won't back legislation financing government agencies unless the bill blocks federal payments to the women's health care provider Planned Parenthood. A partial shutdown will occur Oct. 1 unless lawmakers provide money to keep government functioning.
With time running out, Republican leaders haven't said how they will handle conservatives' demands while also rounding up enough votes to prevent a shutdown.
A look at the undercurrents they face as they work to figure it out:
THE REPUBLICAN PARTY CAN'T IGNORE CONSERVATIVES ...
Conservative and Republican revulsion for Planned Parenthood and abortion has been reignited this summer by secretly recorded videos showing organization officials offhandedly discussing how they sometimes provide tissue from aborted fetuses for medical researchers.
Keeping conservatives happy and prompting large numbers of them to vote in next year's presidential and congressional elections is good for the Republican Party. Conservatives are among the party's most loyal and numerous voters.
Advancing a bill that finances government agencies but blocks Planned Parenthood's money is one way to do that.
BUT REPUBLICANS CAN'T GO TOO FAR
Such a bill probably would pass the Republican-run House. But Senate Majority Leader Mitch McConnell acknowledges that he lacks the votes to prevail in his chamber and says President Barack Obama would veto it anyway.
That makes Republican leaders reluctant to force a doomed standoff with Obama that could result in a shutdown and alienate pivotal independent voters. The public mostly blamed Republicans in 2013 when a partial shutdown lasted 16 days after they tried dismantling Obama's health care law in exchange for keeping agencies open.
"Having charged up the hill once and been shot down, why would you want to do that again?" said Republican Rep. Tom Cole, an ally of House Speaker John Boehner. "I'm pretty convinced we're not going to shut down the government."
Planned Parenthood gets over $500 million in federal and state funds annually, virtually none of which can be used for abortions, and says it's done nothing wrong.
CONSERVATIVES AREN'T MONOLITHIC
Republican Rep. Mick Mulvaney has collected 31 signatures from conservative lawmakers pledging to oppose any bill funding government if it includes money for Planned Parenthood.
Sen. Ted Cruz, a Republican presidential contender, is circulating a comparable letter. Many of the other Republican presidential contenders are also urging Congress to slash Planned Parenthood's funds.
But Republican aides say Cruz has won little support within his Senate caucus. Underscoring tactical differences, abortion foe Sen. James Lankford told Tulsa radio station KFAQ that blocking Planned Parenthood's funds is "a sideshow" to legislation to directly "protect children."
Congressional leaders' immediate problem is Mulvaney. If his group of 31 holds and Boehner wants to pass a bill preventing a shutdown and funding Planned Parenthood, he'd need Democratic votes.
Boehner needed, and got, Democratic backing to end the 2013 shutdown and a brief closure this year of the Homeland Security Department in an immigration fight with Obama.
But no leader likes to battle his own party's members and rely on the other's to pass crucial legislation. Besides, the deep partisan schism over Obama's nuclear weapons deal with Iran -- which garnered zero Republican votes -- spotlights bitter divisions that could hinder Boehner from winning Democratic support.
A COUP AGAINST BOEHNER?
Boehner has clashed often with some of the House's most rebellious conservatives. This summer, Republican Rep. Mark Meadows introduced a symbolic motion to remove Boehner from the speakership. It went nowhere but conservatives might force a binding vote on deposing Boehner and think that threat could pressure him to avoid working with Democrats.
"The last thing we need is more weak leadership from John Boehner" with a possible vote to oust him "always stalking out there," said conservative Rep. Tim Huelskamp.
Spokesman Kevin Smith said Boehner "is focused on ensuring that our team is exposing Planned Parenthood's barbaric methods to the world, saving more babies" and said the speaker "is not going anywhere."
It's unclear if an effort to remove Boehner would succeed, but it would be embarrassing.
Boehner retains support from most House Republicans. They respect his leadership skills and close links with the Republican establishment that let him raise an enormous $28 million in the first half of 2015, aides say. He even wins affection from ardent abortion foes like Rep. Trent Franks, who said, "His heart is very open, he's very pro-life and I'm convinced he's trying to do the right thing."
THE PATH FORWARD
It's unclear. Republican leaders will likely seek to temporarily finance government, perhaps setting up a Christmas showdown over 2016 spending and Planned Parenthood.
Meanwhile, the House plans votes next week on bills by Rep. Diane Black halting Planned Parenthood's federal funds for a year and by Franks protecting infants born alive during abortions. Both would likely pass the House but face long Senate odds.
The Senate is expected to vote this month on a measure by Sen. Lindsey Graham, a Republican presidential hopeful, barring most late-term abortions. It faces likely defeat.
A vote on another bill cutting off Planned Parenthood's money could come later this year.