But in Sin City, where one can stay in a glass pyramid rising from the Nevada desert, dine under the Eiffel Tower or be serenaded on a Venetian gondola, nothing is ever quite what it seems.

Here in America’s gambling capital, the nation’s fastest-growing metropolis in one of its most unpredictable swing states, where Evangelical Christians and devout Mormons in the north must contend with Vegas’s instant marriage chapels and casinos in the south, Ms Sanchez is electoral gold dust. Democrats wager that she can help to defeat President Bush this November.

Ms Sanchez, Mexican but now a US citizen, is one of the hundreds of thousands of Hispanic and Latino voters who have flocked to Las Vegas since the 2000 presidential election, looking for work in a city that has 14 of the world’s 15 largest hotels and thousands of bars, casinos and nightclubs. In 1990 one in ten residents in Nevada was Hispanic, a voting bloc that tends towards the Democratic. They account for one in five residents . In Clark County, home to Vegas and 1.6 million of Nevada’s 2.2 million people, this huge influx has turned a state won by President Bush four years ago into a place so volatile that John Kerry, the presidential challenger, now fancies his chances.

Mr Bush won Nevada by 4per cent in 2000, but today it is too close to call. The explosion in Hispanic populations in two other southwestern states, New Mexico and Arizona, combined with Nevada, has created a new, three-state electoral battleground known as the “Cactus Corridor”. Mr Kerry and Mr Bush are fighting hard for the region’s precious 20 electoral votes.

Last week one poll put Mr Kerry’s lead over Mr Bush among America’s Hispanics at 33per cent. In Nevada the Kerry campaign, aware that Hispanic turnout in elections is notoriously low (45per cent in 2000), has been frantically visiting shopping malls, hotels and bars. Helped by local unions, they have signed up tens of thousands. Jon Summers, a spokesman for the Nevada Democratic Party, refused to give a precise figure, but said: “In January, there were 13,000 more registered Republicans in Nevada than Democrats. There are now 6,000 more Democrats. We have turned a Republican state Democratic.”

One Hispanic woman said: “There is no protection for us here. No benefits. No job security. Bush does not care about us.”

Mr Bush, however, has prosperity and the northern part of the state on his side. With its huge gambling and entertainment industry, not just in Vegas but in Reno on the state’s northwestern border, unemployment is just 4.2per cent, compared with a national average of 5.5per cent.

Outside Reno and Vegas, among the miners and ranchers who live in Nevada’s vast desert wilderness, voters are fiercely conservative, although they represent just a quarter of the electorate. “If northern Nevada were more populated, then probably Republicans would feel better about their chances,” Jennifer Duffy, a political analyst, said.

Nevada also has an odd mix of cultural conservatism and libertarianism that might favour Mr Bush. From the governor’s office down, all six state executive offices are held by Republicans.

But perhaps the most unwelcome joker in the pack for Mr Bush is the issue of Yucca Mountain, 100 miles north of Vegas. Mr Bush supports a plan to bury America’s nuclear waste there, after promising in 2000 that he would never support the plan unless it was “sound science”.

The plan is fiercely opposed by 70per cent of Nevadans, both Republicans and Democrats. But, as President, Mr Bush has always played a high-stakes game, something they understand in Nevada.

THE STATE OF NEVADA

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