Dean Heller. David Calvert/Getty Images Sen. Dean Heller of Nevada told reporters on Friday that he will not vote for Senate Republican leadership's healthcare bill as it stands now.

"It's not the answer, it's simply not the answer," Heller said. "In this form, I will not support it."

Heller is up for reelection in 2018 in a state won by Hillary Clinton in last year's presidential election. Nevada also expanded the Medicaid program under the Affordable Care Act, or Obamacare, and the Senate bill would phase out that expansion starting in 2020.

Heller said he can't support a bill "that takes insurance away from tens of millions of Americans and hundreds of thousands of Nevadans."

The senator also said that he wants to bring down insurance premiums, which the bill doesn't do.

"There isn't anything in this bill that would lower premiums," Heller said.

Heller's opposition is the latest roadblock for the Better Care Reconciliation Act (BCRA). On Thursday, the same day it was released, four conservative senators — Rand Paul, Mike Lee, Ted Cruz, and Ron Johnson — also came out against the bill. That group said the legislation did not go far enough in its repeal of Obamacare.

Due to unanimous opposition from Democrats, Republican leaders can afford no more than two Republican defections for the bill to pass.