In less than an hour, a bill to avert a government shutdown has gone from the House to the Senate and, finally, back to the House.

Shortly after 9:25 p.m. ET, the Senate voted to kill two House-passed amendments that chip away at Obamacare, which the House had passed less than an hour before. That puts the Senate's co-called "clean" CR back in the House less than three hours before a midnight shutdown deadline.

Senate Democrats' rejection of the House bills had been forecast before the House even voted on them.

"We will be right back at square one yet again. House Republicans simply have to choose whether to put the Senate’s clean CR on the floor and let it pass with Democratic and Republican votes, or force a Republican government shutdown," a senior Senate Democratic aide said.

The House passed two changes to Obamacare in its continuing resolution by a 228-201 vote. It delays by one year the implementation of the individual mandate, and it includes language that would bar lawmakers, Congressional staffers, and administration staffers from receiving federal subsidies for health insurance under Obamacare.

Earlier on Monday, the Senate made the same move, killing two GOP amendments that the House passed Saturday night.

After the House vote, Senate Majority Leader Harry Reid quoted Albert Einstein's definition of insanity and said, "Republicans have lost their minds."

The Senate then voted, 54-46, to table the amendments.