By Wayne Cole

SYDNEY (Reuters) - Share markets were whipsawed, while bonds and the dollar rose on Wednesday as results from the U.S. presidential election proved far closer than polls had predicted, potentially leaving the outcome in doubt for days to come.

Democratic contender Joe Biden took to the air to declare he was still optimistic about winning and called for all votes to be counted, no matter how long it took.

President Donald Trump responded saying that he had won, that "they" were trying to steal the election, without providing evidence, and that he would go the U.S. Supreme Court to fight for the win if needed.

Investors had initially wagered that a possible Democratic sweep by Biden could ease political risk while promising a huge boost to fiscal stimulus.

But the mood quickly changed as Trump snatched Florida and ran much closer in other major battleground states than polls had predicted.

U.S. equity futures went on a wild ride, rising then falling, climbing again as the voting seemed to favour Trump before buckling again in tandem with European futures after Trump vowed to make a Supreme Court challenge.

"It means possibly quite a lot of volatility," said AXA Group's Chief Economist Gilles Moec in London.

"As it is not clear, markets are going to overreact to every tiny piece of news," such as any further talk from Trump or Biden about legal fights.

(For the latest results and news on U.S. election, click: https://www.reuters.com/world/us-election2020 )

Dealers said investors could be thinking a status quo result would at least lessen political uncertainty and remove the risk a Biden administration would roll back corporate tax cuts.

The technology sector seemed encouraged, with NASDAQ futures rising as much as 2.2% at one point before easing back to 0.6% upNQc1. E-Mini futures for the S&P 500 dropped 1% though after Trump's news conference. EUROSTOXX 50 futures were last down 1.6% having been fractionally higher just 30 minutes earlier.

Andrew Brenner, head of international fixed income at NatAlliance Securities, said the move in techs looked like it was a play on the Senate potentially staying Republican.

Brenner said that under a Biden win tech stocks were seen faring worse, partly due to Democrats going after the sector in hearings and also that a potential rise in capital gains tax would hit tech stocks harder.

Japan's Nikkei .N225 was ahead by 1.7%, while MSCI's broadest index of Asia-Pacific shares outside Japan edged up 0.2%.

Chinese blue chips rose 0.7%, with markets uncertain how Sino-U.S. relations would develop from here.

Some investors were now hedging against the risk of a contested election or at least a drawn-out process as mail-in ballots were counted.

"It's a wait-and-see," said Matt Sherwood, head of investment strategy at Perpetual in Sydney.

"I think the odds of a clean (Democrat) sweep are diminishing, almost by the minute. That reduces the possibility, or the likelihood at least of a large stimulus program being agreed to in the first days of a Biden administration."

That saw 10-year Treasury yields fall all the way back to 0.81%, having been at a five-month top of 0.93%.

The U.S. dollar had a roller coaster session, reversing early losses to be last up 1% on a basket of currencies at 93.902 =USD. The euro fell back hard to $1.1640 and away from a top of $1.1768.

The chance of a Trump victory saw the dollar jump 2% on the Mexican peso on the assumption U.S. trade policies would continue to favour tariffs. Norway's crown and Australia's risk-sensitive dollar both tumbled too.

Going the other way, the dollar eased 0.9% on the Russian rouble which had been one of the hardest fallers in the run up to the election.

STILL TO COME

Investors are still awaiting the outcome of U.S. Federal Reserve and Bank of England meetings this week, which are expected to at least give a nod to further stimulus.

The Reserve Bank of Australia on Tuesday cut interest rates to near zero and boosted its bond-buying program, adding to the tidal wave of cheap money flooding the global financial system.

Gold had recently been buoyed by all this liquidity but ran into profit-taking on Wednesday, losing 0.6% to $1,896 an ounce.

Oil prices held gains made after industry data showed crude inventories in the United States dropped sharply.

Dealers noted a returned Republican administration would likely be more positive for the oil industry than Democrats that favoured renewable technology.

U.S. crude futures were up 90 cents at $38.56 a barrel, with Brent crude futures gaining 91 cents to $40.62.

(Reporting by Wayne Cole; additional reporting by Gui Qing Koh, editing by Richard Pullin, Sam Holmes and Kim Coghill)