Mr Trump offered his condolences to Mr McCain – a frequent critic of the President – as he recovered in Arizona from emergency surgery for a blood clot.
“We hope McCain gets better very soon, because we miss him,” Mr Trump said at an event promoting his “Made in America”-themed week. “He’s a crusty voice in Washington. Plus, we need his vote.”
“He’ll be back soon,” the President continued. “But we need that vote, and we need a number of votes, because we do have to repeal Obamacare.”
Mr McCain’s sudden absence from the Senate has stalled the GOP plan to repeal and replace Obamacare – a legislative victory both the White House and Republicans in Congress are eager to claim.
Without Mr McCain, however, Republicans are dangerously low on votes in favour. Republicans need 50 votes to pass the Better Care Reconciliation Act, meaning they can only afford two defections. Senators Rand Paul and Susan Collins have already declared their opposition to the bill, making Mr McCain’s support crucial.
Senate Majority Leader Mitch McConnell postponed the vote on Saturday, saying: “While John is recovering, the Senate will continue our work on legislative items and nominations.”
A statement from Mr McCain’s office suggested he would be away from the floor for only a week, but experts told The New York Times it may be longer.
Democrats, in the meantime, are demanding public hearings on the bill in the Senator’s absence. Republicans fear the delay will only serve to make the bill – which currently has a 17 per cent public approval rating – even more unpopular.
“I think the longer the bill’s out there, the more conservative Republicans are going to discover that it’s not repeal, and the more that everybody’s going to discover that it keeps the fundamental flaw of Obamacare,” Mr Paul said on CBS News’ “Face the Nation” on Sunday.
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Mr McConnell has already scrapped plans for a health care vote once before, when the bill failed to garner adequate support last month. The GOP debuted a new version of the bill last week, but a handful of Republicans remain uncertain.
Mr Trump is said to be putting pressure on Senate Republicans to toe the party line, reportedly even meeting with candidates to run against deflectors in the midterms.
“The Republican senators are great people, but they have a lot of different states,” Mr Trump said on Monday. “…But we’re getting it together, and it’s going to happen.”