WASHINGTON — After a campaign that drove a deep wedge between them, President Obama is now trying to rebuild relations with the business community in hopes of enlisting it in his showdown with Republicans in Congress over the looming fiscal crisis.

Through phone calls, White House invitations and old-fashioned political flattery, Mr. Obama has dispensed with some of the populist language of the campaign trail to appeal to corporate America’s palpable desire for certainty. In groups and one by one, the president is making a case to business leaders that siding with him will put the nation back on a firm fiscal footing and unleash the economy.

“What’s holding us back right now, ironically, is a lot of stuff that’s going on in this town,” Mr. Obama told the Business Roundtable, a group of corporate leaders, on Wednesday. “And I know that many of you have come down here to try to see, is there a way that we can break through the logjam and go ahead and get things done? And I’m here to tell you that nobody wants to get this done more than me.”

White House officials have been encouraged by what they describe as a more positive reaction than expected. Many chief executives who met with Mr. Obama privately at the White House last week told him they would go along with his proposal to raise taxes on the wealthy. And several have come out publicly for the plan as long as there is also an effort to tame the growth of entitlement spending.