The Democratic unemployment insurance plan has been agreed to on a party line vote of 50-49. 

By voting to pass this amendment, introduced by Sen. Ron Wyden, Democrats have now superseded the Portman unemployment insurance amendment that passed Friday night.

-ABC News' Allison Pecorin

The Senate has passed the Portman unemployment insurance amendment by a vote of 50-49. 

Sen. Joe Manchin, D-W.Va., was the only Democrat to vote with Republicans in favor of the amendment.

While the Portman amendment passed, it is expected to be superseded by the Democratic agreement on UI Saturday morning. 

It's still unclear when Democrats intend to offer their superseding amendment.

-ABC News' Allison Pecorin

After eight hours of inaction, Democrats have reached an agreement among themselves on how to proceed with jobless benefits with Sen. Joe Manchin, of West Virginia, on board.

Senate Democrats will now offer an amendment to extend the enhanced UI program through Sept. 6 at $300 per week, according to a Democratic aide. The House-passed bill was through Aug. 29.

The agreement also provides tax relief to workers who received unemployment insurance compensation by making the first $10,200 of UI benefits nontaxable for the first time to prevent surprise bills for the unemployed at end of year, which was not in the House-passed legislation. The provision applies only to households making under $150,000.

The agreement also extends tax rules regarding excess business loss limitations for one additional year through 2026.

-ABC News' Trish Turner

Several Republican senators held a press conference Friday evening as the Senate entered its fifth hour of being paralyzed over how to proceed on amendments related to unemployment insurance. (It's now been about six hours since the last vote was called). 

The Republicans said that a handful of moderate Democrats -- including Sen. Joe Manchin, D-W.Va. -- are being "worked over" by Democratic leadership and told that they cannot vote with Republicans on Sen. Rob Portman's, R-Ohio, amendment that would reduce weekly jobless benefits to $300 and end the program in July. Democrats have their own amendment that would reduce the jobless benefit to $300 weekly but extend the program through September and make the first $10,200 paid out untaxable.  

Sens. Lindsey Graham, R-S.C., and John Thune, R-S.D., both said they believe Biden is speaking with moderate members over the phone and pressuring them not to vote with Republicans -- though ABC has not confirmed that.

"It's now five and half hours actually since the last vote started. And because there was an amendment that we were prepared to offer that actually had bipartisan support, the Democrats have actually gone back behind closed doors and - as Senator Graham pointed out - tried to get the president on the line to try to pressure a couple of people not to work with Republicans," Thune said.

Graham said the stall makes Biden's call for unity on inauguration day "ring hollow" and that Democrats who may support the Portman amendment are being punished for bipartisanship. 

"This break out of bipartisanship has lead to the Senate coming to a halt because they want it their way or no way," Graham said. "There is some bipartisanship we believe to change the bill, but apparently that's an unpardonable sin on the other side. We believe we have some Democrats who read the bill yesterday and found some things they didn't like, sat down with some Republicans to find a better way and the result is we've done nothing for four hours and 20 minutes to break somebody's political arm." 

Thune, the Republican whip, conceded that he does not yet know if there would be enough Republican support on the Portman amendment to pass it, but he does believe there are several Democrats who might support it.

-ABC News' Allison Pecorin