Democratic White House contender Barack Obama expressed confidence on Monday that a rejected bailout package would still get through Congress and urged markets to stay calm.
At a rally in Westminster, Obama also scorned Republican rival John McCain's claims of leadership over the financial crisis and said his very philosophy of economic management had been exposed as bankrupt.
The Democrat said he had been on the telephone with Treasury Secretary Henry Paulson and House of Representatives Speaker Nancy Pelosi along with other congressional leaders.
"They are still trying to work through this rescue package," the senator said after the House rejected the $700-billion package in a dramatic vote.
"I'm confident that we're going to get there but it's going to be a little rocky," Obama said.
"It's important for the markets to stay calm because things are never smooth in Congress and to understand that it will get done."
Shares on Wall Street tumbled by nearly 700 points as the bill appeared headed to defeat and then recovered some 200 points as the vote was finalised.
In scenes of rare suspense on the House floor, sworn Republican foes of the government's intervention and rebel Democrats combined to doom the bill by 228 votes to 205, after President George W Bush had pleaded for its passage.
"Right now Democratic and Republican leaders have agreed but members have not yet agreed. There's going to be some bumps and trials and tribulations and ups and downs before we get this rescue package done," Obama said.
"One of my messages I have to Congress is, get this done.