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With government departments and agencies officially in shutdown mode Tuesday morning, the warring parties on Capitol Hill appear just as entrenched as they did when the standoff started.

Senate Majority Leader Harry Reid has called the Senate back into session at 9:30 a.m., but the Democrats signaled no changes to their strategy of holding firm against any changes to President Obama's signature health care law.

"This is an unnecessary blow to America," Reid said on the Senate floor shortly after midnight as the shutdown began to take effect. Republicans, he said, are "fixated on embarrassing our president."

Republicans also seem immovable.

Asked how he sees the shutdown getting resolved, House Majority Leader Eric Cantor told ABC News in the early morning hours of Tuesday, "it's really up to the Senate" to determine whether they are prepared to negotiate with Republicans."

Meanwhile, the House of Representatives adjourned after 1 a.m. and is scheduled to reconvene at 10:00 a.m. House Speaker John Boehner left the Capitol without an agreement in place to open it back up. Asked whether he was prepared to vote on a clean continuing resolution - the option that even some Republicans acknowledge is the only way out of the shutdown - Boehner maintained that Republicans "are hoping that the Senate will take our offer to go to conference."

Boehner and the Republican leaders in the House are insisting on a conference with the Senate - even announcing a team of eight Republicans, including Cantor; House Ways and Means Committee Chairman Rep. Chairman Dave Camp, R-Mich.; and House Budget Committee Chairman Rep. Paul Ryan, R-Wisc. - who would lead the negotiations.

But that may not happen at all.

In a speech on the Senate floor late Monday night, Reid emphasized that he would not appoint negotiators to work with the other chamber unless they passed a six-week emergency spending bill without any provisions relating to delaying or defunding Obamacare.

"We will not go to conference with a gun to our head," the Nevada Democrat said.

Republicans balked at Reid's hard line.

"I already heard Harry Reid on the floor saying he didn't want to sit down and discuss things or resolve it. I just think that's unacceptable to the American people," Cantor told ABC News early Tuesday. "I mean the president likes to say that he won the election, but you know what? The people also elected a Republican House, and I think that the American people expect us to sit down and talk with one another."

The path toward ending the shutdown remains uncertain, with neither side signaling they are ready to buckle. But it's becoming clear that the Senate has far less of the stomach to fight than the House. Several Republican senators told ABC News that the House position was untenable.

"We can't win this fight," Sen. John McCain said, calling on GOP leaders in the other chamber to send the Senate a bill to fund the government - without a poison pill of delaying Obamacare attached.