Still, with 535 members of Congress attending the joint session, the number who had publicly committed to the display of comity was a relatively small fraction. And some made clear that they would sit where they always have: among members of their own party.
"I'm heading to the right," Rep. Tim Scott of South Carolina told ABC News' "Top Line" today.
"Southern boy from North Charleston, South Carolina, we sit to the right, we even lean to the right. So at the end of the day I'm going to the right," he said.
House Speaker John Boehner did not weigh in publicly on the seating proposal. But he ended up sitting beside Vice President Joe Biden on the speaker's platform, consistent with tradition.
Senate Majority Leader Harry Reid had only said that the plan should receive "serious consideration" but did not publicly reveal plans to partner with a Republican ahead of the speech.
"More important than the appearance of sitting together is what we do together," said Senate Minority Leader Mitch McConnell, who did not cross the aisle for the State of the Union address. "And the American people are more interested in actual accomplishments on a bipartisan basis here in the next six to nine months than they are with the seating arrangement at the State of the Union."
McConnell and other GOP aides have noted that lawmakers have always been free to sit where they want and that this year was no different. Seating for the speech is first come, first served, and it's likely many members simply sat next to colleagues of the opposite party whether they wanted to or not.
But while some questioned whether the seating plan signaled true willingness to tone down rhetoric and openness to legislative compromise, many lawmakers said it couldn't hurt.
"It is a symbolic gesture, but why not start with a symbolic gesture?" Murkowski said. "Why not start off this new 112th Congress with a gesture, an effort, to try to come together even for just a couple hours?"
"If we can't sit together on an important night like this, how can we face the challenges that the country has?" Udall asked. "We're committed to having the kind of debates around here where you can disagree without being disagreeable."
ABC News' Matthew Jaffe and Jonathan Karl contributed to this report.