Kyrsten Sinema, Arizona’s Democratic senator who beat her Republican rival turned seat mate Martha McSally last year, is not staying out of McSally's 2020 race.

Sinema’s campaign blasted out a fundraising email last week telegraphing her desire that the state’s other Senate seat be won by “someone who shares our values.”

The email doesn’t name names, but it’s widely known that Sinema does not see eye-to-eye with McSally, who is running in the state's 2020 special election.

“Arizona is poised to be the primary battleground for control of the Senate AGAIN,” the Sinema email says. “We need to immediately reignite the grassroots movement we build (built) last year to ensure that Arizona’s junior Senate seat goes to someone who shares our values.”

Sinema’s campaign has “launched a Battleground Arizona Fund to ensure we have the resources to keep building our movement heading into 2020,” the email says.

Though McSally lost the 2018 race to Sinema, she was appointed to the seat long held by the late Sen. John McCain, R-Ariz. To hold onto it, McSally must win the special election in 2020. She appears poised to face-off against retired astronaut Mark Kelly, whose fundraising about doubled McSally’s during the first quarter.

Neither has drawn a competitive primary challenger in the special election.

A spokesperson for Sinema’s campaign declined on Monday to talk about the fundraising email and her potential plans for 2020.

A spokeswoman for McSally declined to comment. A spokesman for Kelly did not respond to The Arizona Republic's request.

Arizona’s Senate race could be key in determining which party controls the Senate in 2020. Political analysts are sizing it up as a toss-up, given Sinema’s 2018 win by more than 2 percentage points, the state’s growing population of people of color, and President Donald Trump’s divisive presidency.

Trump won Arizona by just 3.5 percentage points in 2016 over his Democratic opponent Hillary Clinton.

McSally has largely aligned herself with Trump. Kelly is casting himself as a centrist Democrat, much like Sinema.

More than $121 million was spent during last year’s Senate battle, according to data through December from the Federal Election Commission and the Center for Responsive Politics.

That tally includes more than $69 million from outside groups, $24 million from Sinema and $20 million-plus by McSally and the other candidates.

“You can bet that the same out-of-state mega donors who spent millions to try to defeat Kyrsten are already lining up to do it again this cycle,” Sinema’s fundraising plea says.

“... Contribute today so we can go toe-to-toe with the massive amounts of money about to flood the race for Arizona’s Senate seat.”

Have news to share about Arizona's U.S. senators or national politics? Reach the reporter on Twitter and Facebook. Contact her at yvonne.wingett@arizonarepublic.com and 602-444-4712.

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