Tony Krvaric knew he wasn't going to get much help from the national presidential campaign in his effort to get people to the polls to boost local GOP candidates to victory.

So the San Diego County Republican Party chairman spent more than $15,000 on Mitt Romney bumper stickers, lawn signs and other campaign swag to motivate voters and volunteers.

"There's a lot of enthusiasm for Romney and Ryan, and I want to tap into that," Krvaric said. "That will help all my local candidates."

No matter what happens nationally, the presidential race is all but decided in California, with President Barack Obama maintaining a double-digit lead in the polls. Yet how well the rivals perform could tip the scales in the state's most competitive congressional and legislative races.

The narrower Obama's win in the state, the better for GOP candidates on the rest of the ballot. An electorate that resembles the voter makeup in 2008 could boost down-ticket Democrats.

"It's huge," said Democratic pollster Ben Tulchin, who is surveying voters in swing districts. "We're taking a very close look at how big a margin Obama wins by and turnout."

While political experts know California's 55 electoral votes aren't in play, the presidential race is still the top draw for many voters watching the tight national contest. Some candidates say they feel swings in the national campaign on the ground.

Rep. Dan Lungren, who is locked in a close race with Democrat Ami Bera in the 7th Congressional District, said he saw a "notable increase in enthusiasm" after Romney delivered a strong performance in the first presidential debate.

"When I walk precincts people come and tell me, after Romney's performance, 'Man, I've got to get out there and do it,' " the Gold River Republican said.

With both presidential candidates devoting little time or resources in California, some get-out-the-vote efforts are emphasizing the importance of local races and big ballot measure fights.

Bera said he thinks heavy spending and attention surrounding the 7th Congressional District has put the House race at the top of voters' minds. With Obama safely in the lead in the state, the Elk Grove Democrat is banking on his campaign's own grass-roots operation, which has grown to more than 1,500 active volunteers, to get supporters to cast a ballot in the close race.

"We've always known that the presidential race would not really play out in a big way in California, that President Obama would obviously carry the state, so from day one we've really focused on building our own field organization and get-out-the-vote effort," he said.

Campaigns in other swing congressional districts are reminding voters of what's at stake in Congress.

Democratic Rep. John Garamendi, who is facing a challenge from Republican Kim Vann in the 3rd Congressional District, called California "the step in the West to push back against" policies embraced by Republicans controlling the House as he spoke to volunteers preparing to walk precincts on his behalf.

"Here in Sacramento, you are right smack in the epicenter of the hottest congressional races in this nation," the Walnut Grove Democrat told the crowd at a labor rally. "And we've got our hands full here."

Republicans are also making House races a top priority. The California Republican Party has teamed up with the National Republican Congressional Committee to open more than a dozen "Victory" offices throughout the state. Independent groups such as the U.S. Chamber of Commerce and American Action Network, a nonprofit associated with House GOP leadership, are spending heavily to reach voters in those races, often highlighting unpopular political moves by House Democrats.

Whether voters are inspired to cast a ballot for president could have the biggest impact in areas heavily populated by demographic groups less likely to vote, such as young people and minorities. Both of those groups voted in higher-than-usual numbers in 2008, when turnout in California hit more than 79 percent of registered voters.

"In a district where the Democratic base is very, very strongly ethnic and low income and younger, then you're going to see that volatility on the presidential race impact the state races more," said Paul Mitchell, a former Democratic consultant now serving as vice president of Political Data Inc.

Several competitive seats in the Central Valley fit that profile, including the 10th Congressional District race between Rep. Jeff Denham and Democratic challenger Jose Hernandez.

While national polls show an extremely tight presidential race, the overall margin between Obama and Romney hasn't changed much in California in the final month of the campaign. Public Policy Institute of California President Mark Baldassare said it's possible that Californians are insulated from national trends in the polls because they aren't on the front lines of the campaign.

"Our votes aren't at play, there's not a lot of visits from the candidates in which a lot of time there's interaction with the public, a lot of air time on radio, TV, billboards, things like that," Baldassare said.

Polling released last week did suggest enthusiasm among Republicans has grown. The percentage of GOP voters polled by the PPIC who were satisfied with their presidential candidate choices has increased four percentage points to 69 percent since September. Democrats' satisfaction levels dropped one point, to 77 percent.

That's exactly the sort of shift that political operatives like Krvaric want to inspire. The San Diego GOP chairman sees opportunity in the relative silence from the top of the ticket because voters aren't sick of the telephone calls and television ads from the presidential campaigns. He finds people are more receptive when the caller begins by talking about the Romney-Ryan campaign.

"In Nevada, you're hanging up if someone calls from Romney-Ryan or Obama or Biden. You're like, leave me alone already," Krvaric said. "But people here haven't been called. Nobody has called the poor people in Poway to ask them what they think about the presidential race. They're so excited."

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