A return to partisan form may be just around the corner, but Democrats and Republicans joined together on Tuesday to hail the inauguration of President Barack Obama, the first African-American to reach the White House, and to heap praise on the first speech of his presidency.

Obama’s former Congressional colleagues mostly commended his 18-minute address as a measured, sober assessment of the challenges facing the country that mixed themes of uplift with a call to arms and shared sacrifice.

“I think his message was to the point, and I think he’s looking forward to the challenge and we look forward to working with him,” Sen. Saxby Chambliss (R-Ga.) said. “I think you know it’s reality time now.”

Carrying the same sentiment of another young Democratic-Senator-turned-president’s inaugural appeal to “ask not what your country can do for you,” Obama’s speech “laid out the challenge that confronts us, which is surely going to include some unpleasant moments,” said Rep. Richard Neal (D-Mass.), a leading member of the House Ways and Means Committee. That panel on Thursday morning will mark up an $825 billion stimulus package, an initiative emerging as the first major test of Obama’s presidency.

“The message has been sent that we’ve all got to do this and it’s a very heavy lift,” Rep. Gwen Moore (D-Wis.) said. “I got my orders, my papers, from listening to the president, that I have got to do my part as a Member.”

Rep. Phil Hare (D-Ill.), a home-state colleague of Obama’s, heard a similar message: “He was challenging us, too. He was saying this isn’t going to be easy, and we’ve got to step up.”

Not everyone was gushing, however. Sen. John McCain (R-Ariz.), whom Obama defeated for the presidency, had only this to say in reaction to the day’s events as he headed into a bipartisan lunch with his one-time rival: “I don’t have any comment.”

The two clashed on the campaign about how hawkish American foreign policy should be as the nation faces frayed foreign alliances and depleted resources as a result of two wars but the continued threat of terrorism. Obama’s address sent an unmistakable signal that he intends to restore some international goodwill lost in President George W. Bush’s years by relying more heavily on talks with foreign governments to solve conflicts.

House Republican Conference Chairman Mike Pence (Ind.) said he interpreted the speech as a veiled shot at Bush’s foreign policy record. “Our first priority is for America to be respected in the world, especially by our enemies. And our second priority should be how much we’re liked,” he said.

But Pence said he helped lead the standing ovation for Obama’s message to terrorists that, “You cannot outlast us, and we will defeat you.”

Other Republicans — and most Democrats — lauded Obama for his tough talk on foreign policy while also calling for greater diplomacy in dealing with other nations. Sen. Mike Crapo (R-Idaho) said he was “pleased” that Obama expressed a desire to “reach out where we could but that we expected those who were acting inappropriately to realize that we would not tolerate that.”

Likewise, Sen. Ben Nelson (D-Neb.) said the speech told the world: “You’re on notice. We want to be your friend, but don’t be our enemy.”

But even with crises of enormous proportions threatening the nation at home and abroad, lawmakers of both parties took a moment on Tuesday to revel in the historic nature of the first African-American president.

Obama only briefly alluded to his race during his speech, describing himself as a “man whose father less than 60 years ago might not have been served at a local restaurant.” But the fact was at the front of many minds, including those of his former colleagues in the Congressional Black Caucus. Rep. Elijah Cummings (D-Md.), a past CBC chairman, said that during Obama’s speech he thought of his 82-year-old mother, a former sharecropper. “And I was just so grateful that in the twilight years of her life, she was able to witness this,” he said.

Rep. John Lewis (D-Ga.), a civil rights icon who shared the stage with Martin Luther King Jr. during his “I Have a Dream” speech 45 years ago, said he was “overcome” by Obama’s words and reflected on the progress made toward racial equality since King’s speech.

“I kept thinking about what he said,” Lewis said of King. “It all paid off. It was all worth it.”

And the day frequently had a post-partisan — or at least bipartisan — air worthy of Obama’s campaign pledge to change the tone in Washington. Before the swearing-in, Members gathered on the House floor to divide up by class — at one point bursting into a bipartisan happy birthday serenade of Rep. Shelley Berkley (D-Nev.) — and then chatted with their classmates as they filed outside to the risers.

After the swearing-in, Obama and top members of his administration joined leaders from both parties for a lunch in Statuary Hall. Pence said he chatted privately with Obama during the event, and he “expressed his desire to continue to reach out to House Republicans, and I told him how much we appreciated that, welcome that.”

Obama’s efforts to soften old partisan divisions in Congress are already off to a shaky start, however. Republicans are attacking the House Democrats’ plan to try to jump-start the economy as irresponsibly pricey. And they are crying foul that the majority cut them out of talks to develop the package, a move that GOP leaders said undercuts Democratic pledges to give them more input.

Some think Obama is willing to steer the package in a direction more to their liking. “I’m very hopeful that will happen,” House Minority Whip Eric Cantor (R-Va.) said.

But on the larger point, Pence said Democratic leaders on the Hill need to follow Obama’s lead in order for a different kind of politics to take root. “The degree to which any bipartisanship goes forward will have as much to do with the posture of Congressional Democrats as it does with the new occupant of the Oval Office,” he said.

Jennifer Bendery contributed to this report.