A bipartisan effort to stabilize Obamacare’s health-insurance markets has collapsed as top Republican and Democrat on the Senate’s health committee were not able to reach an agreement on the proposal. Sen. Lamar Alexander (R-TN), the committee’s chairman, had been working with Sen. Patty Murray (D-WA), the ranking member, on a bipartisan bill following four hearings that were held earlier this month to examine ways to prevent premiums from skyrocketing in 2018. “During the last month, we have worked hard and in good faith, but have not found the necessary consensus among Republicans and Democrats to put a bill in the Senate leaders’ hands that could be enacted,” Alexander said in a statement. Earlier Tuesday, Alexander seemed pessimistic about the prospects of reaching a deal, blaming Democrats for getting behind a single-payer health care system and Republicans for reviving repeal-and-replace efforts. “The current hang-ups are that we’re trying to find a bipartisan consensus in an environment where suddenly Sen. Sanders and 15 Democrats are promoting Medicare for All, Republicans are trying for repeal-and-replace, the majority leader says he won’t put it on the floor, the House speaker says he won’t pass it, and the president says he won’t sign it. Other than that, that’s a pretty tall amount to climb through,” Alexander told reporters at the Capitol.