Republicans are accusing Democrats of purposely slowing an agreement on federal spending and Zika control to keep the GOP off the campaign trail.

Talks have dragged on for days after a deal was expected pass the Senate and head to the House as early as last week. The slowed negotiations have dashed the GOP's hopes for an early exit.

Senate Majority Whip John Cornyn, R-Texas, said Democrats are stalling a deal to keep vulnerable Senate Republicans from returning home to campaign for re-election. The Senate majority is at stake, and with more than half a dozen very competitive GOP seats in play, Democrats stand a strong chance of retaking the gavel.

"The problem is they would like us to stay around for a while because our 2016-ers, they don't want them to be at home campaigning," he said. "They've got nobody in jeopardy so it seems like that is what is happening."

Senate Democratic aides point out that the schedule envisioned the Senate being in as late as Oct. 7. Still, Democrats have few reasons to rush home and plenty of motivation to keep the Republicans from leaving Capitol Hill. Most importantly, incumbent Democrat senators have no close races to sweat.

The lone toss-up seat held by a Democrat is in Nevada, and its current occupant, Senate Minority Leader Harry Reid, doesn't need to rush home to campaign because he is retiring.

The slowed talks on a funding package will keep the Senate in until next week, Majority Leader Mitch McConnell, R-Ky., announced Tuesday. But Cornyn said the agreement is nearly finished and "we could get it out of here by the middle of next week."

Republicans believe Democrats have been taking their time finalizing the agreement because recent polling has shown their prospects of taking over the Senate majority next year have diminished over the past few weeks. "Dems, seeing latest polling and momentum shift, now stalling to keep GOP members in DC," Cornyn spokesman Drew Brandewie tweeted on this week.

Democrats reject the GOP theory, and say they are simply unable to reach a deal with the GOP on a short-term government spending bill that includes money for battling the Zika virus. Reid blamed Republicans for adding "vexatious, poison-pill riders" to the legislative package.

But Reid is now complaining about existing law. He wants Republicans to alter a provision blocking the Securities and Exchange Commission from forcing public companies to disclose campaign spending. That provision, Republicans noted, is part of the fiscal 2016 spending law and would be included in a short-term spending bill that automatically carries over the law from the previous year.

Reid has defended the move to alter the SEC language.

"We're not going to have this bill be a pin cushion for McConnell's desire to have nothing, nothing reported dealing with campaign spending," Reid said Tuesday. "Corporations can give under the present law lots and lots of money and it doesn't have to be reported. The SEC has the ability to change that."

Democrats may have another reason to stall the spending deal. They are in no hurry to move on to a veto override vote on a bill allowing the families of the victims in the Sept. 11, 2001 terrorist attacks to sue the Saudi Arabian government.

If they stall the spending bill long enough, Republicans could decide to postpone that vote until after the election. That would help the Democrats because a veto override vote that would show a split in the Democratic Party.

The legislation received unanimous support in the House and Senate and lawmakers are poised to override President Obama's veto, a first for his administration. Obama has not yet sent the veto message despite a Friday deadline.

"Why are you waiting, Mr. President?" Cornyn said. "Veto the bill if that's what you've decided to do … and send it back to us so we can have the vote to override that veto, which I'm confident we will."

Democratic leaders have been vague on how they will vote, underscoring the political quandary caused by the pending veto message sent by their party leader.

President Obama is opposed to the bill because he believes it would undermine the relationship between the United States and the Saudis, who are key U.S. allies. The administration has warned it could leave the United States vulnerable to foreign lawsuits.

"I haven't made a final decision on it," Senate Minority Whip Richard Durbin said.

Minority Whip Steny Hoyer, D-Md., said President Obama has "a legitimate concern," with the legislation and "most members" agree with him.

"I don't want to prejudge what we will do," Hoyer said. "I want to see the president's veto message first. We all voted for this."

Obama must veto the bill by Friday, but it is unclear how long the paperwork will prevent it from arriving in Congress, a GOP leadership aide said.

Cornyn said the Senate will not leave until it votes on Obama's veto message. But House Speaker Paul Ryan, R-Wis., didn't guarantee the House will vote.

Whether the House takes up the veto override, Ryan said Wednesday, "depends on the Senate timing," and "how long it takes for us to get our other work done. If we are in, and they pass it, then it's going to come over here and we'll pass it."