The last time Ruben Gallego made national headlines for launching a Democratic campaign, he did it with five words on Twitter.

Back in 2014, the then-state representative had assembled no large-scale campaign team, had no detailed polling on his electoral chances and had no sophisticated roll-out.

“I am in for Congress,” wrote Gallego, in announcing his bid for Arizona’s reliably blue 7th Congressional District.

Now, he is in the final stages of deciding whether he will run for the Democratic nomination for U.S. Senate in 2020, a process that is outwardly more deliberative than his first gut-instinct announcement for a national post.

Gallego, a Latino Marine Corps combat veteran of the Iraq War, declined to comment about the factors he is weighing as he decides whether he will join retired astronaut Mark Kelly in the Democratic field for the race.

But interviews with about a dozen of his supporters, current and former campaign staff members and volunteers and Democratic officials reveal that Gallego is gearing up to run, giving Democrats something they have rarely had over the past 25 years, a true competitive Senate primary. Democrats attracted a crowded field in 2010, but one has to go back to the 1994 primary between then-Rep. Sam Coppersmith and Secretary of State Richard Mahoney for one that featured a comparable rivalry.

Speed was necessary for Gallego in 2014 because he needed to lay down a marker immediately after then-U.S. Rep. Ed Pastor announced his retirement.

When Gallego does make an announcement for Senate one way or another, he will do so in a way that does not step on festivities surrounding the swearing-in of his ex-wife, Kate, who was elected Tuesday as mayor of Phoenix. She is scheduled to be sworn in on March 21.

Gallego team has messaging ready 'if we press go'

If Gallego waits until after the end of the month to announce he is running, he would have more time to raise money before his campaign’s financial performance would be made public through quarterly filings with the Federal Election Commission.

Kelly has seen early fundraising success, putting him on par with some presidential contenders. In a race that has already attracted national attention,Gallego would be under pressure to quickly demonstrate that he, too, can generate the same level of enthusiasm.

Behind the scenes, away from the visible efforts by liberal groups to draft him into the Senate race, Gallego is talking to potential supporters and prospective campaign staffers about what a race against Kelly would look like.

Gallego has not recorded videos to announce his decision, but his team has developed some messaging reflecting what a potential progressive campaign would look like.

Gallego has mused in blast emails about the need for another demographic breakthrough in the Senate for an Arizonan. The state hasn't had a Hispanic senator.

For Gallego, it's an appeal to the Democratic Party's younger, more diverse voters who could help tip a primary. Over the past several weeks, he has made clear to friends and associates during casual conversations that he intends to run.

There is no official launch date.

Andy Barr, a Democratic consultant who has worked for Gallego, said the congressman has done nothing that commits him one way or another for a Senate race.

“... But I think he’s sort of gone up to the edge of having something ready if we press go," he said.

Ally says Gallego is 'going for it'

Steve Gallardo, a Maricopa County supervisor and longtime Gallego supporter, recalled a conversation he had with the congressman in late January following Martin Luther King Jr. Day celebrations.

“We were at Margaret T. Hance Park. I asked him point-blank what his plans are, and he told me, 'I’m running,''' Gallardo recalled. “He’s going for it … He didn’t hesitate. It wasn’t like, ‘Oh, I’m thinking about it. I’m talking to people.’ It wasn’t that type of discussion. It was, ‘I am running.'''

Felecia Rotellini, Arizona Democratic Party chairwoman, is preparing for a robust primary.

Asked if Gallego has informed her of prospective Senate plans, she responded, “I’ve talked to Ruben, and he’s told me he is preparing his candidacy for the U.S. Senate.”

With the race 18 months away, she said Gallego is under no pressure to make a decision quickly.

“There will be plenty of time to announce, and both Mark Kelly and Ruben Gallego have very high-profile stories,” she said. “The fact that Ruben may take time to make a decision, I don’t believe, will hurt his chances.”

Rotellini dismissed the notion that a competitive Democratic primary would divide the party and hurt its chances of taking the seat.

Perhaps, but there are still Republicans who think the drawn-out GOP primary in 2018 may have cost McSally conservative votes in a November contest settled by 2 percentage points.

Gallego and Kelly are “skilled and mature, and will make wise decisions about how they will run their campaign,” Rotellini said.

Democratic primary could benefit Republicans, some say

Outside groups supporting incumbent Republican U.S. Sen. Martha McSally hope Gallego gets in the race, if only to highlight the Democratic Party’s leftward swing under President Donald Trump.

If McSally does not draw a competitive challenger, a spirited Democratic primary would give Republicans a months-long advantage to raise money and reintroduce the retired combat pilot and two-term congresswoman to Arizona voters.

Republicans would be less worried about facing Gallego in a general election than Kelly, who is trying to stake out a moderate campaign void of party labels, said Annie Vogt, a Phoenix-based GOP strategist.

“In a general election, what we’ve seen is voters want a more centrist, moderate, pragmatist candidate, which is why I think they’re (Republicans) are hoping that Gallego jumps in,” Vogt said.

McSally was appointed to the Senate seat once held by the late John McCain after losing her 2018 Senate race to Democrat Kyrsten Sinema, who distanced herself from her party and ran essentially as a third-party candidate.

The website Sabato’s Crystal Ball has classified the 2020 Senate race a toss-up while the Cook Political Report deems it as “leans Republican.”

McSally faces different political dynamics as she heads into her second Senate bid.

This time, Trump will be at the top of the ticket. He won Arizona in 2016 over his Democratic challenger Hillary Clinton, by 3.5 percentage points. McSally will have the advantage of incumbency. And she may not have to waste time or money battling a right-of-center primary challenger, as she did in 2018.

Jim Pederson, a retail developer, Democratic donor and former chairman of the state Democratic Party, has talked with Kelly and Gallego about their plans and describes them both as friends.

Kelly, Pederson said, “is going to have to really sell the people about why he shares their views on the issues.”

No one doubts Gallego’s bona fides as a Democrat given his longtime involvement in the party, his time as a congressman, and his vocal criticism of Trump.

“If had to guess, I’d say there’s a pretty good chance he’s going to run,” said Pederson, who unsuccessfully challenged then-U.S. Sen. Jon Kyl, R-Ariz., in 2006. “I think he’s committed to that. Now, anything could happen between now and the time that he announces that could change that.”

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