Ted Cruz and Donald Trump are now running neck and neck among Republican voters in California, with Florida Senator Marco Rubio still within striking distance in third place.

The Field Poll released on Tuesday shows Cruz at 25 percent and Trump two points behind him, while Rubio received 13 percent.

The poll also reveals political neophytes and onetime strong contenders Ben Carson and Carly Fiorina have slipped to nine and three percent, respectively, significantly down from their average polling of 14 percent back in October. Former Florida Gov. and previous front-runner Jeb Bush is also languishing far behind at just four percent.

Meanwhile, Cruz has gained nearly 20 points since October and is now also twice as likely as Trump to rank as California Republicans' second preference.

"What you see is that beyond just the horse race, where (Cruz) is in a statistical tie with Trump, he seems to be much better positioned to be the beneficiary of the declining fortunes of other candidates," Field Poll director Mark DiCamillo said. "He seems to be the candidate who is best positioned to capture even more support from other candidates as the field winnows."

Though California stands out as a lucrative donor state in presidential politics, what impact it will truly have on the 2016 race remains somewhat in question given the lateness of the state's actual voting season.

"By the time we get to California, if there is still a race going on -- and maybe there will be this year -- the field will be smaller," DiCamillo said. "It'll be three, four or five candidates at the most."

Trump's many controversial statements, particularly about immigration, have generated more anxiety about his candidacy than other candidates, with 43 percent of likely Republican voters saying they would be dissatisfied or upset if he won the party's nomination.

Earlier in his campaign, Trump boasted if elected he would move to deport some 11 million immigrants in less than two years.