The strategy emerged after Republicans barely succeeded earlier this week in opening debate on health legislation in the narrowly divided Senate, winning the procedural vote to do so thanks only to Vice President Mike Pence breaking a 50-50 tie. On Tuesday, on a 57-43 vote with nine GOP defections, the Senate rejected a wide-ranging proposal by Majority Leader Mitch McConnell to erase and replace much of the Affordable Care Act. [...] with President Donald Trump sitting in the Oval Office and itching to sign it, Republican senators demonstrated they didn't have the stomach to go through with passing a measure that would end insurance coverage for more than 30 million Americans over a decade, according to the Congressional Budget Office. The measure has not been finalized, but senators say it could eliminate Obamacare's two mandates — for individuals to carry insurance and for employers to offer it — along with an unpopular tax on medical devices, and perhaps contain a few other provisions. Under the complex rules governing how the legislation is being considered, the debate will culminate at some point Thursday afternoon or evening in a bizarre exercise called a "vote-a-rama" during which unlimited amendments can be offered by all sides in rapid succession.