A science-advocacy political action committee backing retired NASA astronaut Mark Kelly has released a Democratic firm's poll that it claims suggests Republican Martha McSally, Kelly's potential 2020 Senate opponent, is the most vulnerable U.S. senator going into the 2020 election cycle.

The automated statewide telephone poll was conducted by Democratic polling firm Public Policy Polling. It was organized by 314 Action, a non-profit organization that compares itself to the liberal group EMILY's List in its ability to get pro-science candidates elected.

Only 40 percent of the 682 Arizonans polled said they would vote for McSally, Arizona's junior senator while 54 percent indicated they "think it's time for someone new." The other 6 percent of respondents said they weren't sure.

McSally has only been in the Senate since Jan. 3. She lost last year's hard-fought Senate race against Democrat Kyrsten Sinema, who now is Arizona's senior senator. But McSally ascended to the Senate anyway after Gov. Doug Ducey appointed her to fill the seat vacated by retiring Sen. Jon Kyl, R-Ariz.

The poll's margin of error was plus or minus 3.8 percentage points. The survey was conducted Jan. 24 and Jan. 25.

The Arizona Republic's requests for comment on the poll from McSally and her team were not successful.

314 Action already has announced it is endorsing Kelly, citing his experience in the Navy, NASA and gun-safety advocacy. The poll's release appears aimed at nudging him into the race.

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Kelly, who is married to former Democratic U.S. Rep. Gabrielle Giffords, has not officially announced a Senate run, but he has met with the Democratic Senatorial Campaign Committee, sparking rumors that he is interested in competing for McSally's seat.

"Captain Kelly has committed his life to public service, which is why 314 Action and the voters of Arizona are calling on him to continue that commitment and run for the United States Senate in Arizona," Ted Bordelon, a group spokesman, said in a written statement.

The poll targeted Arizona voters' feelings about McSally and President Donald Trump.

More respondents said they would consider re-electing Trump than McSally, but Trump still trailed an unnamed "Democratic opponent" 50 percent to 46 percent. The other 4 percent was not sure.

In the 2016 election, Trump carried Arizona by 3.5 percentage points against Democratic rival Hillary Clinton.

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