In tone and substance, the two speeches marked a change in the campaign rhetoric that has held sway since the weekend, when a furor erupted over Obama's remark that residents of small towns cling to religion and guns out of bitterness over their economic plight.
Clinton and her campaign surrogates have criticized him virtually nonstop in the days since, suggesting he is an elitist who would lead the party to defeat this fall.
For his part, Obama has struggled to overcome the fallout from the worst gaffe of his 15-month campaign for the White House, and on Sunday, accused Clinton in turn of posing as a supporter of gun rights despite her longtime record in favor of gun control.
If the personal rhetoric was tempered, the Clinton campaign signaled it was not ready to let go of the issue.
Late Monday, aides unveiled a new television commercial that they said will run in Pennsylvania. It features several unidentified younger men and women criticizing Obama for his remarks. "It just shows how out of touch Barack Obama is," says one man.
Obama countered with an ad of his own. It asserts that voters are rejecting Clinton's attacks, and shows him saying, "When we get past the politics of division and distraction and we start actually focusing on what we have in common, there's nothing we can't accomplish."
Frank's comments were the latest in a string of signals from party officials who are eager for the nominating campaign to end so the party can unify for the fall campaign against McCain. If anything, his remarks carried extra weight because of his long-standing support for Clinton and his status as a superdelegate.
In recent weeks, party officials who are neutral have called for a reasonably quick end to the campaign.
Senate Majority Leader Harry Reid of Nevada has said he hopes a winner will emerge quickly after the final primaries, and Speaker Nancy Pelosi of California said she does not believe the nearly 800 superdelegates should overturn the verdict of the voters.
Once the prohibitive front-runner, Clinton's hopes of winning the nomination now rest on her ability to finish the primary season with a series of strong victories, beginning next week in Pennsylvania.
She then must persuade enough superdelegates — party officials who are not picked by the voters — that she is a more electable candidate than Obama, and overtake him in the weeks immediately after the primary season ends on June 3 in Montana and South Dakota.
So far, despite the furor over his remarks, Obama has not lost the public support of any previously committed superdelegate.