A bipartisan group of senators ended a long-running election-season standoff and struck a compromise that would extend jobless benefits for 2 million Americans who have been out of work the longest, the lawmakers said Thursday.

Should the Senate approve the election-year measure — as seemed likely — it would throw the issue to the Republican-run House. Its fate there was uncertain. The timing of a Senate vote also was unclear.

Two leaders of the negotiations —Sens. Jack Reed, D-R.I., and Dean Heller, R-Nev. — said in a statement that the deal would be retroactive to the end of last year, when the emergency benefits program expired. Since then, the benefits have ended for roughly 2 million people.