CHICAGO (Reuters) - A bill package aimed at ending Illinois' record-setting budget impasse and addressing the state's deep fiscal woes will not be voted on in the Senate until the second week of February, the chamber's leaders announced on Thursday.

The delay poses the risk of another credit rating downgrade for Illinois, which is already the lowest-rated U.S. state.

Democratic Senate President John Cullerton and Senate Republican Leader Christine Radogno had aimed for votes this week on the 13-bill package they unveiled earlier this month.

Cullerton said members should be prepared to vote when the Senate returns to session on Feb. 7.

"If we need more time to pull this together, I'm going to consider that encouraging," he said on the Senate floor.

Radogno gave what she called "a little pep talk," telling members she believed both caucuses want to end up with a sustainable balanced budget for the nation's fifth-largest state.

"Just because we are not taking a vote today absolutely does not mean that our efforts are becoming unraveled," Radogno said.

The delay pushes a potential budget fix past an end-of-January deadline set by Fitch Ratings, which has warned that a lack of a comprehensive budget solution will result in a downgrade of Illinois' low-investment grade BBB-plus rating.

"We are going to review the rating by the end of January," Fitch analyst Karen Krop said Thursday.

The state's ratings have been cut by the three major credit rating agencies five times under Governor Bruce Rauner.

The Republican governor on Wednesday cheered on the Senate's efforts in his annual State of the State address, while not explicitly throwing his support behind the legislation.

Since taking office in 2015, Rauner has feuded with the Democratic-led state legislature, leaving Illinois as the only U.S. state to go 19 months without a complete budget.

The Senate's bipartisan budget omnibus would raise income taxes by a third, borrow $7 billion to winnow down a record-setting pile of unpaid bills and open Chicago for the first time to legalized casino gambling.

It also includes items on Rauner's wish list, including a possible fix for the state’s $130 billion pension crisis, changes in how workers are compensated for on-the-job injuries and the imposition of term limits on legislative leaders.

(Reporting by Karen Pierog and Dave McKinney; Editing by Matthew Lewis)