WASHINGTON, July 17 (Reuters) - Senator John McCain, a critical vote in the U.S. Senate's healthcare overhaul, was described as upbeat and comfortable in Arizona on Monday but was still days away from traveling to Washington after surgery to remove a blood clot from his head.
The Arizona senator underwent surgery on Saturday to remove a clot above his left eye discovered during a physical examination, forcing Senate Majority Leader Mitch McConnell to postpone a healthcare vote and throwing the timing of the debate into uncertainty.
In the meantime, the White House continued its efforts to persuade uncommitted Republican senators to vote for the legislation, with several senators set to dine with President Donald Trump on Monday evening.
McCain's support is vital for the bill, which needs the backing of at least 50 of the 52 Republicans in the 100-member Senate. Republicans Susan Collins and Rand Paul already have said they will not vote to open debate on the legislation - meaning one more "no" vote would kill it.
"Senator McCain is in good spirits and recovering comfortably at home with his family. On the advice of his doctors, Senator McCain will be recovering in Arizona this week. As available, more information on Senator McCain's progress will be made public," said McCain spokeswoman Julie Tarallo.
Senator Lindsey Graham, a close friend of the 80-year-old senator, told CNN that McCain had been growing forgetful in recent weeks.
"I'm glad they found out what I think was the cause," Graham said. "After talking to him - I talked to him Sunday - (he was) just like the old John McCain, much more engaged in conversation."
Another friend who had talked to McCain, said "he sounds great" and that he was so eager to get back into the action in Washington that he was musing about the prospect of taking a cross-country road trip.
Changes in cabin pressure associated with air travel could harm the recovery for McCain, who survived a bout of melanoma in 2000. While his office has said the recovery could take a week, medical experts told the New York Times the recovery time for such procedures is often longer.
"We hope John McCain gets better very soon. We miss him," Trump said at a White House economic event.
"He's a crusty voice in Washington, plus we need his vote."
Even with McCain, Republicans face plenty of obstacles to passage of the measure to replace the 2010 Affordable Care Act, popularly known as Obamacare. Democrats are united in opposition to the bill, and Collins estimated on Sunday that "eight to 10" Republicans still have serious doubts about it.
Other Republican senators who have expressed concerns or remain noncommittal include Rob Portman, Mike Lee, Shelley Moore Capito, Dean Heller, John Hoeven, Lisa Murkowski, Jeff Flake, Ben Sasse, Cory Gardner, Todd Young and Thom Tillis.
A Senate Republican aide said senators were reluctant to be the third "no" vote, essentially sinking the bill, so many of the undecideds will hold off until the last minute in declaring their stance.
WHITE HOUSE PUSH
Senator Orrin Hatch, chairman of the Senate Finance Committee, met with White House officials on Monday. Trump plans on holding a dinner at the White House in the evening that congressional aides said would include Senators Lamar Alexander, John Cornyn, Steve Daines and James Lankford, among others.
Cornyn was asked whether the group would discuss how to bring holdouts into the fold. "I hope so," he replied.
An extended delay could endanger passage, as the Senate faces an agenda packed with other legislation and critics of the measure hope to use the delay to increase opposition to it.
Top Senate Democrats sent a letter to Republicans on Monday suggesting they hold a public hearing during the delay, saying it would allow senators to hear "unfiltered and unbiased" feedback on the bill.
The letter also requested that Republicans make a commitment not to proceed on the bill without a complete score from the Congressional Budget Office, which was initially expected to release an analysis on Monday but has delayed that report.
Over the weekend, a threatening note was left at Heller's Las Vegas office. Officers who responded to a burglary alarm at the building found the note near the office door on Sunday morning, police said in a statement on Monday. The content of the note was not released.
New York state Attorney General Eric Schneiderman intends to sue the federal government if Republican lawmakers pass legislation to overhaul the U.S. healthcare system, his office said on Monday.
(Writing by John Whitesides and James Oliphant. Additional reporting by Susan Cornwell.; Editing by Mary Milliken and Jonathan Oatis)