California is determined to force 2020 Democratic presidential hopefuls to make some hard choices.

California, the nation's most populous liberal state, has moved its presidential nominating contest to early in the 2020 calendar.

Leaders hope this shift will give it maximum impact on the selection of a Democratic nominee and push candidates to address progressive issues such as climate change.

The move could also create tension for candidates who simultaneously may be courting more moderate electorates.

WASHINGTON (Reuters) — California is determined to force 2020 Democratic presidential hopefuls to make some hard choices.

The nation's most populous liberal state has moved its presidential nominating contest to early in the 2020 calendar, a shift its leaders hope will give it maximum impact on the selection of a Democratic nominee and push candidates to address progressive issues such as climate change.

The reshuffling means California voters, who can cast ballots weeks before primary election day, will be helping to determine a nominee at the same time as those in traditional early primary states such as New Hampshire.

"It's a big deal," said Ben Tulchin, a San Francisco-based consultant who worked as a pollster for Democratic US Senator Bernie Sanders' 2016 presidential campaign. "The traditional schedule had smaller states, more affordable states, retail politics. California is not like that."

Bernie Sanders speaks at a rally at the University of Massachusetts in Amherst in 2016. Matthew Cavanaugh/Getty Images The shift to so-called "Super Tuesday" in March 2020 will change how campaigns structure their efforts and require tough decisions about allocation of resources, Democratic Party sources and strategists say. Competing in California, with its large, expensive media markets, may only be possible for the most deep-pocketed campaigns.

That factor alone might be enough to keep some of the two dozen or so Democrats who are considering entering the race from getting in.

"The amount of money you're going to need to be competitive in California is just going to knock so many people out before it begins," said James Demers, who was co-chairman of Democratic President Barack Obama's campaign in New Hampshire. "It feels like the day and age of using Iowa and New Hampshire to get a campaign started are over."

Read more: An early look at the 2020 presidential contenders

Those two states have zealously guarded their position as the points of entry for presidential aspirants. But with their small and largely homogeneous populations, they may be more a part of the Democratic Party's past than its future, as liberal elements within the diverse party have pushed to have a bigger say in the selection of a nominee.

In the 2016 race, the two states combined to apportion 68 Democratic delegates to presidential candidates. California, the biggest prize, awarded 475.

The candidate who amasses the majority of delegates will be formally nominated at the party's convention in the summer of 2020 and then likely will face President Donald Trump, a Republican, in the general election as he seeks a second term.

A larger playing field

California's secretary of state, Alex Padilla, made clear in an interview with Reuters that the primary was moved up to require contenders to campaign and invest in the state.

For years, California Democrats have complained that candidates came to the state to raise money from the entertainment and tech industries without its voters playing a meaningful role in the outcome of the race.

California secretary of state Alex Padilla. AP Photo/Darron Cummings "Anybody who is running for president who cares about getting votes in California will chose to campaign here," Padilla said. "Those who don't chose to campaign here — that sends a very strong message, regardless of party."

Padilla said the shift also was intended to push candidates to address the issues that concern Californians such as environmental protection, climate change, and immigration, which could end up benefiting candidates with a more progressive agenda that matches the state's left-leaning electorate.

That could create tension for candidates who simultaneously may be courting more moderate electorates in places like New Hampshire and South Carolina or force them to limit their appeal to one faction of the Democratic Party over another.

Michael Ceraso, who ran Sanders' operation in California, said the primary will be a referendum on the state's political priorities. "Do you support the California progressive agenda?" he said.

But it isn't only California that could reshape the nomination process. Delegate-rich states such as Texas and North Carolina also are scheduled to hold a primary on Super Tuesday, significantly widening the battlefield.

The result could be a Democratic field reduced to a handful of candidates a month after the primaries begin in early February. (The full primary schedule will not be finalized until 2019.)

"A clustered calendar has tended to produce an early winner," said Josh Putnam, a political scientist at the University of North Carolina-Wilmington and an expert on the primary process.

Read more: Beto O'Rourke is not qualified to run for president. And that's why he might be the best bet for the Democrats

Candidates will have to map out an expansive, multistate strategy that involves personal campaigning in some states, organizing a field operation in others and launching broadcast and online ad blitzes in still more.

The prospect of competing in California and other Super Tuesday states means candidates likely cannot afford to wait to raise money and build an organization, suggesting a flurry of campaign announcements could come early next year, strategists say.

Risk and reward

Some campaigns will have to determine whether to try to compete in California at all or risk ceding delegates from the state entirely. Under Democratic Party rules, candidates in most instances must amass at least 15% of the vote in a given primary to be awarded delegates.

Complicating the matter could be the presence in the field of Californians including US Senator Kamala Harris, Los Angeles Mayor Eric Garcetti, and billionaire Tom Steyer.

Tom Steyer introduces a panel during the National Clean Energy Summit 6.0 at the Mandalay Bay Convention Center on August 13, 2013 in Las Vegas, Nevada. Isaac Brekken/Getty Images for National Clean Energy Summit 6.0 Historically, however, presidential candidates have not been able to rely on local support. As recently as 2016, US Senator Marco Rubio lost his home-state Florida Republican primary to Trump.

Strategists say candidates cannot afford to neglect Iowa and New Hampshire. The news media's focus will remain on the winners of those contests, making deep expenditures in California a possible risk without reward.

"If you spend a lot of money in California, and you get a terrible showing in Iowa, odds are you aren't going to do well on Super Tuesday," Ceraso said.

That is why Jeff Link, a Democratic strategist in Iowa who has worked for the presidential campaigns of Al Gore and Obama, argues that early voting in California will make the initial primary states even more relevant, as those voters will be looking to identify front-runners.

"Iowa and New Hampshire will come while people have ballots in their hands," Link said.

Reporting by James Oliphant; Editing by Colleen Jenkins and Jonathan Oatis