The revised Senate healthcare bill is already on the verge of imploding

Skeptical Republican senators bristled a at the newly updated version of the Senate healthcare bill released Thursday morning, putting its future in doubt.

Almost immediately, two Republican senators came out against a procedural vote that would get the bill to the floor of the Senate, meaning Senate Majority Leader Mitch McConnell and GOP leaders cannot afford to lose another vote.

A third GOP defection would prevent the bill from even being considered by the broader Senate and would likely require the Better Care Reconciliation Act (BCRA) to be substantially overhauled - or scrapped.

Here's a rundown of the senators to watch in the debate and their current status on the vote:

• Susan Collins (NO): Collins tweeted soon after the release of the updated BCRA that she would not support a motion to proceed. "Still deep cuts to Medicaid in Senate bill. Will vote no on MTP. Ready to work w/ GOP & Dem colleagues to fix flaws in ACA," Collins tweeted.
• Rand Paul (NO): A long-time critic of the bill, Paul said he would not vote for the motion to proceed soon after the bill came out.
• Rob Portman (UNDECIDED): Portman's office confirmed he was reviewing the bill and would wait for a score from the Congressional Budget Office. His chief concern is deep cuts to Medicaid funding in the bill.
• Lisa Murkowski (UNCLEAR): Despite a substantial kickback for Alaska in the newest version of the BCRA, Murkowski remains on the fence. The senator has taken issue with the BCRA's cuts to Medicaid and the freeze of funding to Planned Parenthood. Murkowski was seen meeting with McConnell and other senators, Dean Heller and Shelley Moore Capito, after the bill's release.
• Dean Heller (UNCLEAR): Heller, who is up for reelection in 2018 in Nevada, a state Hillary Clinton won, has concerns on the Medicaid cuts. He was part of the meeting with McConnell.
• Shelley Moore Capito (UNCLEAR): Capito has expressed similar concerns on the slashed Medicaid funding. Capito was in the meeting with McConnell.
• Mike Lee (UNDECIDED): Lee supported an amendment from Sen. Ted Cruz, which would allow insurers to sell plans that did not comply with Obamacare's regulations. The modified version that was included included in the newest BCRA version did not immediately get Lee onboard. "Just FYI - The Cruz-Lee Amendment has not been added to BCRA. Something based on it has, but I have not seen it or agreed to it." Lee tweeted. "I am withholding judgment and look forward to reading it."