Senate Majority Leader John Thune (R-SD) questioned lawmakers’ ability on Monday to address expiring Obamacare subsidies before they lapse at the end of the year, but expressed cautious optimism that bipartisan negotiations could eventually restart.

Thune said he sees an impending legislative defeat for Democrats as a motivator to return to the negotiating table once the chamber votes down a Democratic bill later this week for a three-year extension of the enhanced premium credits. He cautioned against the prospect of any deal in the Senate’s final two working weeks of the calendar year.