Story highlights A North Dakota Republican senator made his comments at a roundtable and in a statement

John Hoeven said he could eventually support the bill but cited some concerns on costs

(CNN) Sen. John Hoeven is the latest Republican senator to come out against party leaders' plan to repeal and replace Obamacare, sharing his reservations at a roundtable in North Dakota this week.

According to the Bismarck Tribune , Hoeven participated in a discussion at the University of North Dakota School of Medicine on Wednesday. There, he told constituents that he "doesn't support the (health care) bill as it stands," though the Tribune noted that Hoeven also expressed confidence that the bill could be improved, and cited premium costs as an area of concern.

Hoeven's reservations add him to a growing list of Republicans who are withholding their support, further imperiling legislation that already faced long odds. He is at least the tenth GOP senator to say he'll oppose the bill in its current form. With a slim majority in the Senate, Republicans can only afford to lose two of their 52 senators for the bill to pass under reconciliation.

Hoeven's office also put out a statement Wednesday further detailing his position. "Premiums and deductibles in North Dakota and across the nation continue to rise and some areas of the country will be left with little or no insurer competition next year. That is why we're working to reform our health care system. While I do not support the Senate health care bill in its current form, we continue working on the legislation with the goal of providing greater access to health care and more affordable health insurance."

Hoeven's remarks Wednesday seemed to clarify his stance on the bill -- he had issued a noncommittal statement in early June saying that he would "review this legislation," wait for a score from the Congressional Budget Office, and then determine how he would vote. That CBO score showed the Senate Republican health care bill would leave 22 million fewer Americans with health insurance by 2026 than under Obamacare.

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