The U.S. credit rating is far from safe. All three major agencies have negative outlooks on the United States, which suffered its first downgrade in history last year when Standard & Poor's stripped it of its triple-A rating.

But the fiscal cliff is only one event in a series of issues that will see ratings agencies looming over Washington for months.

Investors sold off riskier assets such as stocks on Friday and scooped up safe-havens such as the dollar and U.S. Treasuries after Republican Representative John Boehner failed to find enough support from his own party to push a measure raising taxes on millionaires through the House of Representatives.

With Boehner's leadership as speaker of the House on the line, markets worry he can't get any tax plan through Congress at all - much less the stricter terms Obama wants in what's becoming the latest drawn-out political budget debacle.

Dysfunction in Washington was specifically cited as one of the reasons Standard & Poor's cut the U.S. debt rating to AA-plus in August 2011. The "fiscal cliff" itself will reduce the deficit, but Fitch has said that a continuing political standoff could cost the country its top-notch rating.

"This potential for continued gridlock among legislators could have profound effects for the U.S. economy," Standard & Poor's said in a report after the November elections.

Without a budget deal among lawmakers, the fiscal cliff, a package of $600 billion in automatic tax hikes and spending cuts, will begin to kick in January 1 and could push the economy into recession.

If investor hope is fading, though, the rating agencies still have some confidence. Fitch still sees a compromise before year-end, spokesman Brian Bertsch confirmed. "That base case has not changed" from a previous view, he said.

But failure could lead to a rating cut.

If the fiscal fracas drags into next year and looks set to hurt the economy, "the U.S. sovereign rating could be subject to review, potentially leading to a negative rating action," Fitch said in a report on Wednesday.

Moody's will probably resolve its negative outlook on the U.S. rating in 2013, as well, but how remains to be seen.

A spokesman for Moody's said on Friday that the rating agency's view hasn't changed since it issued a report in September saying that the United States could be off the hook for a potential downgrade if there is a medium-term plan that stabilizes the debt and reduces it as a percentage of GDP.

In the event of a plan without such policies, "we would expect to lower the rating, probably to Aa1," according to the report, co-authored by Moody's lead sovereign credit analyst on the United States, Steven Hess.

Moody's might take some time to assess a plunge over the fiscal cliff - but not beyond 2013.

In contrast, of the three major agencies, Standard & Poor's is the least likely to act soon, since the agency cut the U.S. rating to AA-plus last August after intransigence on the debt ceiling debates dented confidence in policymakers.

(Reporting By Luciana Lopez; Editing by Leslie Adler)

• A Permanent Economic Emergency