WASHINGTON — Senate GOP leaders scrambled Wednesday for a deal to revive their health care legislation, but encountered new obstacles as recalcitrant senators doubled down on their opposition to the bill sought by President Donald Trump. Senate Majority Leader Mitch McConnell of Kentucky was conducting non-stop negotiations behind the scenes, but publicly there was little evidence he would be able to get senators to agree to a new version of the legislation by the end of the week, as he hopes to. Trump, who met with Republican senators on Tuesday, told reporters Wednesday that getting approval of a bill will be “very tough.” But he predicted that Republicans will at least “get very close” and may “get it over the line.” McConnell canceled planned votes on the bill on Tuesday in face of mounting opposition from within his own ranks. If Senate Republicans can forge a new version before the July 4 recess, that would allow the Congressional Budget Office to evaluate the changes while senators return to their states.