House Minority Leader Nancy Pelosi (AP Photo/Cliff Owen, File)

Congressional Democrats are poised to exploit the Republican chaos over the government spending bill that could ultimately lead to a government shutdown.

They’ve already named a price for their support: long-term negotiations over equal increases in domestic and military spending that would bust the sequester caps, in exchange for temporary backing for a short-term continuing resolution (CR) that maintains current spending levels. They don’t want a CR with any unrelated policy riders or attempts to undo any of President Obama’s policy initiatives.

And they want Republican leaders to extend an olive branch, now.

“It’s not going to be a vote for nothing,” said Rep. Rosa DeLauro (D-Conn.). “If you want our votes, talk to us.”

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Talks would mark the first test of Democrats’ ability to unite and strong-arm a victory since DeLauro temporarily scuttled passage of fast-track trade negotiating authority allowing Obama to finish work on the Trans-Pacific Partnership agreement. Republicans ultimately outmaneuvered Democratic attempts to slow the trade deal, but Democrats are united on their spending goals.

Congress has fewer than three weeks to pass a stopgap spending bill before the fiscal year ends Sept. 30. And it’s becoming increasingly clear that Republicans are going to need Democrats if they hope to pass a bill that President Obama will sign.

For Democrats, their demands are hardly a new list. They’ve been reciting it since Obama first threatened to veto any legislation failing to lift the strict spending caps put in place by the 2011 Budget Control Act, which imposed the sequester.

But this is the first time Democrats actually have the real potential for leverage to make Republicans comply.

The Democrats have the upper hand because, once again, Republicans are divided, with a band of House conservatives insisting they won’t vote for a spending bill that includes any funding for Planned Parenthood, which sparked a wave of conservative outrage after the release of undercover footage showing officials talking about using fetal tissue for research.

Similar objections exist in the Senate. But so far, Senate Majority Leader Mitch McConnell (R-Ky.) has repeatedly said it would be futile to try to defund Planned Parenthood via the spending bill because Obama would veto it. He has vowed not to allow a government shutdown.

The House is expected to act first on any spending bill, and it’s in Speaker John Boehner’s (R-Ohio) hands to decide what is included in the legislation, according to several Senate aides.

The Senate is expected to address abortion concerns next week by taking up a bill the House already passed banning abortions after 20 weeks of pregnancy.

A group led by Rep. Mick Mulvaney (R-S.C.) announced Friday that 31 House conservatives signed a letter promising not to vote for any spending bill that includes funding for Planned Parenthood, including a short-term measure. The group may be small, but 31 “no” votes guarantees that Boehner can’t pass a spending bill that Obama will sign on Republican votes alone.

On the House schedule this week are a pair of anti-abortion rights bills: one sponsored by Rep. Diane Black (R-Tenn.) that would defund Planned Parenthood and the other by Rep. Trent Franks (R-Ariz.) that would criminalize the procedure after 20 weeks. The votes are an attempt to give conservatives an outlet for their anger before the spending fight begins.

Even if those efforts succeed, they have virtually no chance of becoming law — meaning Mulvaney and his band of conservatives won’t stop targeting the must-pass government spending measure.

Democrats are ready to negotiate, not the least because they seem to have public support for their position. A recent Quinnipiac poll found that 41 percent of voters would blame Republicans for a shutdown.

Rep. Joseph Crowley (D-N.Y.), the vice chairman of the House Democratic Conference, said his party is benefiting from a defensive position they’ve shared for months.

“Democrats have shown a tremendous amount of discipline, and that has also worked to our advantage,” Crowley said. “I think we stand prepared to do that again.”

House and Senate Democrats have been discussing their priorities and strategy and are in frequent contact with the White House, according to several leadership aides.

The conversations are still casual, including an informal huddle between House Minority Leader Nancy Pelosi (D-Calif.) and Sen. Chuck Schumer (D-N.Y.) on the sidelines of a large gathering in New York over the Labor Day weekend.

Pelosi told reporters on Wednesday that she isn’t drawing lines in the sand or digging in on a negotiating position because Republicans haven’t yet come to the table. But Democrats want to start negotiating a long-term plan for spending increases first.

“We have a September 30 deadline, but that doesn’t mean it’s a starting point,” Pelosi said. “It is a milestone on that path if people are in good faith.”

Pelosi spoke with Boehner this week, but they haven’t started formal spending talks. One of Pelosi’s top deputies, Rep. Chris Van Hollen (D-Md.), who is the top Democrat on the House Budget Committee, said he hasn’t heard anything from Republicans about starting the talks.

For now, Democrats are waiting, and planning.