No politician has had a wilder ride in the GOP's futile effort to repeal Obamacare than the most vulnerable Republican senator

It's been a wild few months for Republican Sen. Dean Heller of Nevada as the GOP has tried and, so far, failed to repeal and replace the Affordable Care Act.

Starting with his June announcement that he could not support the original Senate healthcare bill and leading up to the near-certain failure of the new healthcare bill he attached his name to, Heller has earned the ire of hardline conservatives, moderate Republicans, President Donald Trump, and Democrats.

And he has little - if anything - to show for his efforts.

Adding to the situation is the fact that Heller is the only Republican up for reelection in 2018 from a state that 2016 Democratic presidential nominee Hillary Clinton carried last fall. Already, Heller finds himself trailing his announced primary opponent, Danny Tarkanian, by nine points in a recent poll.

The whirlwind stretch for Heller began in June, when he told reporters that he would not vote for the Senate's initial proposal to replace the Affordable Care Act, also known as Obamacare.

"It's not the answer, it's simply not the answer," Heller said of the bill, known as the Better Care Reconciliation Act. "In this form, I will not support it."

The Nevada Republican added that he couldn't support a bill "that takes insurance away from tens of millions of Americans and hundreds of thousands of Nevadans" and "there isn't anything in this bill that would lower premiums."

His prominent opposition to the bill led to massive blowback from Trump and Trump-aligned forces. A pro-Trump nonprofit launched a $1 million anti-Heller ad campaign in Nevada (with the White House's blessing) over his refusal to back the bill. Those ads were quickly pulled after top Senate Republicans, including Senate Majority Leader Mitch McConnell, voiced opposition to the campaign against Heller.

Then while seated next to Trump during a July healthcare roundtable with Republican senators, the president suggested that Heller would eventually vote for the Senate's bill because, as he joked on camera, "Look, he wants to remain a senator, doesn't he?"

Around the same time, Trump's team pushed Las Vegas casino magnates Sheldon Adelson and Steve Wynn to push Heller on his healthcare vote, as The New York Times reported. Adelson and Wynn, Republican mega-donors who played pivotal roles in helping Trump get elected, were "unhappy" with Heller, as a Heller ally told The Times.

Heller began to change his tune, and eventually backed later versions of the healthcare bill that did not pass when the Senate tried to push through various forms of the legislation, including what was known as a "skinny repeal," later in July.

"Where is Gov. [Brian] Sandoval?" Heller said then, mentioning Nevada's Republican governor, whom he said he would look toward when deciding how to vote. "What does he think? How does he feel about the changes that are occurring?"

But even though Sandoval did not back the bill, Heller voted for it anyway, offering up a non-binding resolution expressing support for Obamacare's Medicaid expansion, which Nevada had accepted. Both his resolution and the skinny repeal bill failed.

Now, Heller has gone as far as to co-author the Graham-Cassidy proposal, attaching his name to another piece of legislation that his governor does not support. The bill would significantly alter Medicaid, turning it into block grants for states.

Heller's healthcare posturing has led to Tarkanian, his right-wing opponent, attacking the senator from the left.

"Now, all of a sudden, he's in favor of a bill that does exactly that and I think cuts it even more?" Tarkanian told CNN. "What you see here is that Dean Heller doesn't have any convictions for the positions he holds and he's willing to change them depending on who he's speaking in front of."

A Heller spokesperson, responding to those comments, told CNN that the Graham-Cassidy proposal is "the best solution on the table for the state of Nevada," calling Tarkanian, the son of legendary UNLV basketball coach Jerry Tarkanian and a five-time electoral loser in the state, a "perennial candidate" who "now apparently opposes the repeal of Obamacare."

Meanwhile, Heller's actual opponent on the left, Democratic Rep. Jacky Rosen, has blasted Heller for the shifts as well, and Democrats have launched a number of attacks on Heller in his home state. In firing back at Rosen, the Heller spokesperson said that she has yet to take a position on the single-payer healthcare proposal offered by Sen. Bernie Sanders of Vermont.