The bill would keep the government operating until Dec. 15 and gut Obamacare.
Sen. Dick Durbin, the Senate's No. 2 Democrat, said Democrats favor a spending bill that would keep the government running until Nov. 15, which would force Congress to work sooner on a more sweeping piece of legislation — known as an omnibus spending bill — that he hopes would reverse some automatic spending cuts known as sequestration.
Despite Cruz' effort, a test vote was set for Wednesday. Reid had filed a motion to proceed to the measure, and under Senate rules lawmakers will vote even if Cruz speaks for hours and keeps the Senate in session overnight.
In one exchange late Tuesday, Durbin mentioned that the Princeton and Harvard-educated Cruz had gone to "some very famous schools," and then pressed the Texan on the fact that the numbers simply don't add up for him to prevail.
Cruz said he wasn't delusional and insisted that his move was the first of many steps to unravel the law.
In another exchange, Sen. Tim Kaine, D-Va., pointed to Obama's re-election as the electorate's word on the health care law. Cruz said Obama was a "far more talented candidate" than Mitt Romney and didn't see the 2012 election as a referendum on the health care law.
The Cruz filibuster echoed the effort of Paul, who in March waged a nearly 13-hour filibuster of John Brennan's nomination for CIA director over the president's authority to use drones in the United States. The Senate eventually confirmed Brennan.
Outside conservative groups that have been targeting Republican incumbents implored their members to call lawmakers and demand that they stand with Cruz and his attack on Obamacare.
"This is the ultimate betrayal," the Senate Conservatives Fund said of McConnell and Cornyn — two lawmakers up for re-election next year — in an email Tuesday morning. They pressed their members to "melt the phones," arguing that "we can't let these turncoats force millions of Americans into this liberal train wreck."