DENVER - Republicans have a problem in Colorado, and her name is Maria Martinez. She's middle-class, Catholic, a mother of four. She describes herself as pro-life and thinks her taxes are too high. So why is she spending a sunny autumn afternoon at a Democratic campaign rally?

She has nothing against Pete Coors, the Republican beer baron running for Colorado's open seat in the U.S. Senate. But the mere mention of Mr. Coors's opponent makes her positively giddy.

"Do you know his last name?" she asks, pointing at the sticker on her blouse. "Salazar. Sal-a-zar. I like a last name with a z. It means he's probably one of us," she says with a self-deprecating laugh. "It's like the Italians. They always end in a vowel, we always have a z."

By "one of us," Ms. Martinez means that Ken Salazar is Hispanic-sort of. The Democratic candidate for U.S. Senate is a fifth-generation Coloradoan whose great-great-great grandparents happened to be Mexican. As a lawyer and rancher who was twice elected state attorney general, he would seem to have little in common with millions of more recent immigrants working in minimum-wage jobs, struggling to get by.

But he does have that z in his name. For voters like Maria Martinez, that may be reason enough to send him to the Senate. "It would make me proud to say we have a Senator Sal-a-zar," she said, emphasizing the Spanish sound of the name. "I could say to my children, 'See, if you work hard and you study your lessons, you might go to the Senate one day.' This is why I love America."

If that's reason enough for voters like Maria Martinez to send him to the Senate, it's also the reason Bush strategists are hard at work to make every vote count not only in the national poll, but in tight races at the local level.

The president has seriously eroded the Democratic hold on the Hispanic vote (his father won 25 percent of the Hispanic vote in 1992; Mr. Bush is polling 36 percent now) and the Centennial State is historically a GOP bastion, going Republican in eight of the last 10 presidential elections. But this year-with the state's Hispanic population nearing 20 percent-Colorado's nine electoral votes are very much in play. Polls show the presidential contest here is too close to call, as are races for the Senate and the House of Representatives. That means both parties have been forced to lavish time and money on a state that-like much of the West-used to be an electoral afterthought. With Oregon, Nevada, New Mexico, and Colorado all considered too close to call, the region looms large on this year's electoral map.

Despite the challenges, Republican officials in Colorado vow to keep their state firmly in the "red zone." The good news for the president is that he is gaining among Hispanic voters-up 1 percentage point in polls over his 2000 draw among Hispanics-while John Kerry is slipping.

A Sept. 30 survey among likely Hispanic voters in Arizona, Colorado, Nevada, and New Mexico showed that Mr. Kerry is attracting only 56 percent of the Hispanic vote, compared to 62 percent for Al Gore four years ago. "These numbers do not bode well for Sen. Kerry," says Antonio Gonzalez, president of the Willie C. Velasquez Institute, which conducted the poll. "Kerry holds a 20-point lead over President Bush, but over the past several elections we've seen the Democratic nominee hold a considerably larger margin. If this year's election is anywhere near as close as the 2000 contest, this margin will probably not be enough."

"I predict President Bush will win, no question about it," says Ted Halaby, the state GOP chairman. "If you look statewide, we still have a registration advantage of 185,000. So if we can just get out our voters, we should have success in statewide races."

Indeed, getting out the vote is priority No. 1 in the closing days of the campaign. Two years ago, a get-out-the-vote effort called the "96-hour project" attracted 1,300 volunteers and was credited with helping to elect a new Republican senator and congressman. So far this year, more than 5,000 volunteers have signed up for the last-minute voter blitz, and party officials are aggressively pushing for more.

At a Sept. 30 debate-watching party in a downtown Denver hotel, Vice President Dick Cheney was the headliner, but new volunteers were the prize. As invited guests squeezed one by one through a security checkpoint, party workers swooped in with clipboards. "Can we sign you up for the 96-hour project?" they asked over and over again, collecting scores of new commitments from voters.

Even with an advantage in voter registrations, however, the path to victory is far from clear. While Republicans do outnumber Democrats, nearly one-third of Coloradoans are registered independents, motivated by current events and local issues more than party loyalty. Restless after eight years of Bill Clinton, independents went strongly for George W. Bush in 2000, lifting him to a solid, 9-point victory over Al Gore. But now the independents are restless again, and GOP leaders think they know why.

"The Iraq war is a big issue," Mr. Halaby acknowledges. "That's probably been the biggest variable that wasn't present four years ago." Fort Carson, near Colorado Springs, has sent more than 12,000 troops to Iraq, and more than 40 of those troops have been killed-a low but insidious casualty rate that keeps John Kerry competitive in the state.

Then there's the economy. Mr. Halaby likes to boast that Colorado's unemployment rate of 5.1 percent is better than the national average of 5.5 percent, but four years ago the state's jobless figure stood at just 2.6 percent. Though the economy seems to have turned a corner-state revenues have been up for the past three years-the loss of 76,000 jobs has left many voters worried about their financial future.

If Mr. Bush faces doubts about the war and the economy elsewhere, what makes Colorado different is a volatile mix of demographics, geography, and local politics. Although Mr. Bush connects with Hispanic voters better than most Republican politicians, Democrats retain a sizeable advantage. Colorado Democrats targeted Hispanics in a registration drive that has netted some 50,000 new voters since January.

What Republicans have in their favor is that Mr. Kerry has failed to win the affection of Hispanic voters. "I don't think John Kerry has ever been able to identify with the Hispanic community," says Bush-Cheney spokesman Danny Diaz. "Kerry's having trouble defining himself out here. There are a lot of folks out here who don't understand him."

That's where Ken Salazar's race for the Senate comes in. By helping to mobilize Hispanics across the state, he gives Democrats hope for a rare trickle-up victory. If Salazar supporters-many of them first-time voters-vote a straight-party ticket in unusually high numbers, they may help Mr. Kerry win here in spite of himself.

The Bush-Cheney team isn't taking the threat lightly. "We're fighting for every single Hispanic vote," says Mr. Diaz. "We have a grassroots network, Spanish-language phone banks, radio and TV interviews on Spanish stations, Spanish-language ads on the air. We're walking neighborhoods, knocking on doors. We're engaged at both grassroots and mass-communication levels. . . . Our challenge is to communicate the clear choice and mobilize the vote."

In addition to winning more Hispanic voters, the GOP needs to turn out large numbers of conservative rural voters. But those efforts, too, may be hampered by the Salazar factor-in this case, John Salazar, a Democratic congressional candidate in the western part of the state and the Senate candidate's older brother.

The elder Mr. Salazar is running for the seat left open by the retirement of Rep. Scott McInnis, a Republican. With a 13,000-voter edge in registration, national Republicans once considered the sprawling 3rd Congressional District relatively safe territory. But Mr. Salazar, a third-generation farmer in a largely agricultural district, has maintained a consistent lead in the polls\. By presenting himself as a moderate, pro-gun Democrat, he's avoided some of the stigma of the national party. Meanwhile, some voters haven't forgiven his Republican opponent, Greg Walcher, for supporting a statewide referendum that many feared would divert scarce water to Denver's growing suburbs at the expense of more rural areas.

A Democratic win in a rural congressional district could spell trouble for Republicans. Democrats outnumber Republicans by better than 2 to 1 in Denver, the state's largest city-an advantage that is usually offset by more conservative voters in the countryside. If those rural voters opt for a Democratic congressman this time around, the GOP must convince them to split their ticket in favor of Mr. Bush and Mr. Coors.

Mr. Diaz believes the Bush message will resonate in the 3rd Congressional District, no matter who wins the race for the House. "What drives turnout in rural areas is the top of the ticket," he says. "On the Democratic side, you have the most liberal member of the U.S. Senate. He voted against the partial-birth abortion ban. He's taken questionable positions on gay marriage. Voted for higher taxes 350 times. On issue after issue, John Kerry has just taken the wrong side. . . . George Bush stands for the tenets that these rural voters support, and the Democratic candidates do not."