WASHINGTON ― Sen. Dean Heller (R-Nev.) is facing an onslaught of criticism from both the left and the right over his shifting stance on health care, and there’s new evidence it’s affecting his standing with Nevada voters.

A poll released Tuesday by Democratic firm Public Policy Polling (PPP), which was sponsored by the pro-Obamacare group Save My Care, found that only 22 percent of Nevada voters approve of Heller’s job performance, compared with 55 percent who disapprove and 23 percent who are unsure.

A similar survey fielded by the same group last week showed Heller at 29 percent approval.

The polls were conducted last week over two days immediately preceding Heller’s vote in favor of the final Republican health care bill.

That bill, a so-called “skinny” repeal of major parts of Obamacare, went down in flames on Friday. It would have left 16 million fewer Americans with health coverage and raised premiums by 20 percent over the next 10 years, according to the Congressional Budget Office.

Heller said he hoped to improve the measure after further negotiations with the House, but it’s unlikely he’ll ever get the chance now that GOP leaders have indicated they prefer to move on to tax reform.

Before shifting tack in his final vote, Heller had opposed several prior Obamacare repeal efforts, citing in part cuts to Medicaid.

Heller was widely seen as one of the most vulnerable Republicans up for re-election in 2018, even before his twisting path on health care.

In June, an internal poll conducted by the respected Democratic firm Anzalone Liszt Grove found Heller in a dead heat with Rep. Dina Titus (D-Nev.), who is said to be considering a Senate run to challenge him. A June PPP poll found him similarly matched with Rep. Jacky Rosen (D-Nev.), who has already jumped into the race. That survey also showed that 35 percent of Nevada voters approved of his performance, while 44 percent disapproved.

Heller’s moves on health care seemed to have made matters worse.

“People are real unhappy with Dean Heller,” Las Vegas conservative talk show host Kevin Wall told NBC Las Vegas on Tuesday. “I think people are tired of politicians like this who are all over the map. They want people to have basic, solid, core beliefs.”

Chuck Muth, a conservative activist in Nevada and former executive director of the state GOP, said he thought that Heller had “completely botched it.”

“I think the damage has been done,” Muth said in an interview with Politico.

Heller’s dance on health care and his latest efforts to restart talks, including signing onto legislation drafted by Sens. Bill Cassidy (R-La.) and Lindsey Graham (R-S.C.) that has been billed as compromise legislation, won him little reprieve from Democrats and progressive groups.

A blistering digital ad released Tuesday by Rosen accused Heller of betraying Nevada voters to gain favor with President Donald Trump. The 60-second spot featured clips of Heller coming out against an initial version of the GOP health care bill, as well as video of Heller sitting and laughing next to Trump at a meeting at the White House last month.

Trump’s allies haven’t done Heller any favors, either. After he loudly denounced the Republican health care bill in late June, a super-PAC supporting the president ran ads in Nevada calling on Heller to stick to his promise of repealing Obamacare. The president later ribbed Heller over lunch as he sat by his side, asking, “Look, he wants to remain a senator doesn’t he?”

Heller’s fate is far from certain. He’s an incumbent with more than three and a half million dollars in the bank, and is likely to receive major support from Senate Majority Leader Mitch McConnell (R-Ky.) and his allies in Washington. Moreover, Heller also bears a reputation as somewhat of a political survivor ― few thought he would win re-election in 2012.

That said, his handling of health care likely made a difficult task even more challenging.

“The reality is that Heller has painted himself into a corner in this health care debacle,” a GOP strategist told HuffPost. “He hasn’t done anything right ... you would have to search high and low to find a more unpopular person in Nevada.”

CORRECTION: A previous version of this story incorrectly referred to Heller as a Democrat. This article has also been updated to include links to additional polls, and to correct a link to a PPP poll.