* Dollar tumbles as Trump beats earlier odds and pulls ahead
* Dollar/yen drops more than 3 pct, euro/dollar up more than 2 pct
* Mexico peso tanks to record low, Swiss franc jumps, loonie hit (Updates prices, adds details and quotes)
By Shinichi Saoshiro
TOKYO, Nov 9 (Reuters) - The dollar took a battering against its major rivals while the Mexican peso plunged to a record low on Wednesday, as global financial markets were rattled by the prospect of a shock win for Republican Donald Trump in the fiercely-contested U.S. election.
Trump scored a series of surprising wins over Democrat Hillary Clinton in battleground states including Florida and Ohio, opening a path to the White House for the political outsider that many saw as inconceivable just few weeks ago.
Stunned markets went into full risk-aversion mode, sending investors scurrying out of the dollar and into perceived safe-havens such as the Japanese yen and Swiss franc. The euro and sterling also rallied versus the greenback.
"I would not say the market is in a panic. The possibility of a Trump win, however seemingly remote at the time, was of course something that was considered beforehand and the market is reacting in line with such a scenario," said Bart Wakabayashi, Head of Hong Kong FX Sales at State Street Global Markets.
"That said, there is still a feeling of disbelief at what is happening," Wakabayashi said.
Trump, an anti-establishment political novice, is seen as a risk to global growth as he has pledged to renegotiate trade deals, impose high import tariffs and stirred fears of a currency war with China.
Clinton is seen by markets as more of a known quantity and likely to ensure political and economic stability.
The dollar was down 2.6 percent at 102.350 yen JPY= after dropping more than 3 percent, in a volatile day that saw it rise to 105.480 earlier, when last-minute opinion polls put Clinton in favour.
The greenback also lost 1.6 percent lower against the Swiss franc, another safe-haven, to 0.9625 franc CHF= . The euro rallied to a two-month high and was last up 1.8 percent at $1.1225 EUR= .
"The catalyst behind the dollar's slide was reports that put Trump ahead of Clinton in the battleground state of Florida," said Junichi Ishikawa, senior forex strategist at IG Securities in Tokyo.
"Risk aversion is in the air with equities tumbling."
The Mexican peso, which has served as a barometer of the markets' expectations for a Trump presidency, handed back earlier gains and plummeted versus the dollar. The peso sank more than 13 percent to an all-time low just below 21.00 pesos per dollar. of live election results: http://tmsnrt.rs/2fxyZV0
Graphic of live market reaction: http://tmsnrt.rs/2fXfo0L
Live Coverage: http://live.reuters.com/event/election_2016
The scene was reminiscent of the turmoil that engulfed global financial markets after the June Brexit vote, when British voters opted to leave the European Union in a decision that wrongfooted investors and bookmakers. MKTS/GLOB
"No one in the market expected the results that we're seeing so far," said Kaneo Ogino, director at foreign exchange research firm Global-info Co in Tokyo.
"Even if in the case there is a Clinton comeback and she wins, the market already has reacted to the point where the dollar would have trouble climbing back. It's mostly algo dealing in the market now, with dealers staying out. It's system trading, and it's hard for anyone to catch up."
The mayhem in markets prompted Japan's top currency diplomat to signal Tokyo's readiness to intervene in currencies as the yen soared.
"(Currency) moves are quite rough," Masatsugu Asakawa, vice finance minister for international affairs, told reporters, adding that he was watching markets with a "sense of urgency." has pledged to renegotiate the North American Free Trade Agreement (NAFTA) with Mexico and Canada, a move that could damage the economies of the export-heavy U.S. neighbours.
The Canadian dollar CAD=D4 fell to an eight-month low of C$1.3525 per dollar.
The dollar index fell to a one-month trough, shedding 1.4 percent to 96.551 .DXY Sterling was up 0.7 percent at $1.2470 GBP=D4 .
The Australian dollar, sensitive to shifts in risk appetite, fell 1.6 percent to $0.7637 AUD=D4 . The Aussie sank 4.3 percent to 78.25 yen, after briefly sinking to its worst intraday loss since May 2010.