Former Vice President Joe Biden speaks during an Oct. 23, 2019, campaign event in Scranton, Pa. (AP Photo/Matt Rourke) Sen. Elizabeth Warren, D-Mass., speaks during a gun-safety forum in Las Vegas on Oct. 2, 2019. (AP Photo/John Locher) Democratic presidential candidate Sen. Bernie Sanders, I-Vt., speaks during the Climate Forum at Georgetown University in Washington on Sept. 19, 2019. (AP Photo/Jose Luis Magana)

(CN) – Former Vice President Joe Biden has a distinct edge over his nearest Democratic rivals, U.S. Senators Elizabeth Warren and Bernie Sanders, in a poll of likely Arizona voters released Tuesday.

Biden was the choice of 28% of voters in the Emerson Polling questionnaire, conducted Oct. 25-28 online and via landlines. Warren and Sanders polled at 21% each, while South Bend, Indiana, Mayor Buttigieg drew 12% support among Democrats.

Warren and Biden tied President Donald Trump at 50% in a hypothetical head-to-head matchup, while Sanders polled 49% to Trump’s 51%.

No other Democrat among 17 named in the poll drew more than 5% support, and “Someone Else” got 2% support – more than the eight candidates who received zero percent support, including New Jersey Senator Cory Booker, former Housing and Urban Development Secretary Julian Castro and billionaire investment firm founder Tom Steyer.

Although the Arizona Republican Party may not even hold a primary in 2020 – an effort is afoot to cancel it to ease the path for Trump – the poll showed 89% of Republicans would vote for the president, while no other candidate drew 5% support.

Arizona’s Senate race between former astronaut Mark Kelly and former Air Force combat pilot and current U.S. Senator Martha McSally is a dead heat, according to Emerson.

McSally drew 45% support to Kelly’s 46% in a race that has drawn national attention and money. McSally lost a Senate bid in 2018 to Democrat Kirsten Sinema before Gov. Doug Ducey appointed her to fill the vacancy left by the death of Senator John McCain.

Emerson also asked voters to rank issues.

Thirty-three percent put the economy at the top, 18% named health care, and 13% immigration. Impeachment was the top issue for 8% of voters, and 7% thought the environment is most important.

When asked about health care, 45% of Democrats and 14% of Republicans favor Medicare for all. Forty-two percent of Republicans and 12% of Democrats think we should keep the system we have.

“Interestingly, the health care policy at issue is President Obama’s Affordable Care Act, and in Arizona, a plurality of Republicans want to keep the current health care policy as is, while Democrats overwhelmingly want to change the current policy,” said Emerson Polling director Spencer Kimball in a statement.

Though 50% of respondents disapprove of how the president is doing his job, just 43% favor impeachment, the poll showed.

In advance of the 2018 elections, Emerson Polling, housed in Boston’s Emerson College School of Communication, created a new polling method combining online panels and automated landline calls.

The method put numerous pre-election Emerson polls within 1 percentage point of actual results, including California’s gubernatorial and Senate primaries and Pennsylvania’s 18th, Arizona’s 8th and Ohio’s 12th district House seats. The firm saw a 93% accuracy rate among 54 polls in 20 states.

The October poll was among 901 likely voters.