HOUSTON — As he began his closing statement at a forum here Tuesday night, Democratic U.S. Senate candidate Chris Bell seemed to sum up well the mood around the long-uncertain primary.

“I thought we were going to wake up to sunshine this morning since the cloud of Beto O’Rourke had been lifted off of this race," Bell said to some knowing chuckles in the crowd, which had gathered in a Houston church on a rainy evening. "That was not to be, but in all seriousness, the filing deadline has passed, the field is set, and I think it’s time that we get down to business."

The forum, hosted by Indivisible, fell just about 24 hours after the filing period ended for the 2020 elections — and with it, the speculation that O'Rourke could make a late entry into the Senate primary after his exit from the presidential race last month. Democrats now officially have their work cut out for them as a dozen candidates — some more serious than others but no clear frontrunners — vie for the chance to face U.S. Sen. John Cornyn, R-Texas, despite universally low name ID and modest fundraising at best.

Tensions in the field have run mostly low, but that is beginning to change. At least one candidate, Latina organizer Cristina Tzintzún Ramirez, has started moving more aggressively to distinguish herself, while additional areas of potential scrutiny have begun to emerge around other candidates. Tzintzún Ramirez has increasingly found a foil in rival MJ Hegar, who is holding firm on a general election-focused campaign while resisting the progressive impulses that Tzintzún Ramirez and some others have shown.

To that end, Tzintzún Ramirez's credentials are getting a boost Friday with the endorsement of the Working Families Party, a labor-aligned third party that backed Bernie Sanders for president in 2016 and is supporting Elizabeth Warren for 2020. The group, which has an increasingly active Texas chapter, shared the endorsement first with The Texas Tribune.

"We think she's the true progressive in the race, and that's why we're getting behind her," said Jorge Contreras, the party's Texas state director. "We've worked with Workers Defense and Jolt" — two organizing groups that Tzintzún Ramirez helped start — "and we see that she's actually been throwing down for a long time in the state."

Tzintzún Ramirez is campaigning on "Medicare for All," a Green New Deal and a mandatory buyback program for assault weapons — all proposals that Hegar has not embraced or has even overtly rejected. Hegar, an Air Force veteran, is touting herself as neither a moderate nor a progressive but an "ass-kicking" working mom with broad appeal. For months, she has talked openly about training her campaign exclusively on beating Cornyn, ignoring primary rivals and declining opportunities to criticize them.

On a conference call with reporters after filing Monday, Hegar said she had no plans to change that approach as the primary gets closer and the field remains muddled, saying, "This is who I am, and who I am is not interested in taking shots at people who share my values" and are also trying to "move the needle."

Still, Hegar's strategy ran into some controversy a couple of days later when she was asked about Tzintzún Ramirez suggesting the primary was coming down to her and Hegar — and Hegar replied, "Well, it is a two-person race. It's me and John Cornyn." While Hegar added that she was not taking the primary for granted, Tzintzún Ramirez's campaign fired back in a fundraising email hours later that said it "seems like MJ forgot that Cristina was most recently shown to be leading this primary, or that there’s a diverse crowd of other incredible Democratic candidates running too." (The campaign was apparently referring to a November poll that had Tzintzún Ramirez in the No. 1 spot but within the margin of error of other candidates clustered in the single digits.)

It was not the first time there was friction between the two in recent weeks. After Hegar reiterated to The Dallas Morning News in late October that she does not support mandatory buybacks for assault weapons — an idea that O'Rourke championed in his White House bid — Tzintzún Ramirez pushed back in a pointed tweet that said, "Our children's lives are on the line. This isn't a time for political caution." So did Bell, the former Houston congressman, who released a straight-to-camera video saying he was "incredibly disappointed" by Hegar's stance and tweeted that he is "100% with Beto on this one."

To be sure, other contenders, such as state Sen. Royce West of Dallas and Houston City Councilwoman Amanda Edwards, have stopped short of backing mandatory buybacks, only going as far as to support an assault weapons ban. And Bell and Tzintzún Ramirez are not the only candidates in favor of mandatory buybacks — so is Sema Hernandez, O’Rourke’s 2018 primary opponent, who is a vocal advocate of many of the same issues that top Tzintzún Ramirez’s platform.

Hegar's supporters brush off the growing scrutiny, noting she is the fundraising leader in the primary — $2.1 million raised as of last quarter — and arguing she will be the strongest Democrat against Cornyn with her resources and ability to appeal to independent voters and even Republicans. They point to her military background as well as her stronger-than-expected performance in a traditionally red congressional district last year, losing by fewer than 3 percentage points to Rep. John Carter, R-Round Rock.

"I think she's the frontrunner — I thought that before, and I think that now," said Jon Soltz, chairman of VoteVets, Hegar's earliest national endorser. "When you have a huge state with a lot of media markets, it's gonna come down to who voters get to know first. MJ's raised more than anybody else."

Soltz said his group considers Hegar a progressive — and argued such distinctions are irrelevant if a candidate does not have the resources to compete. "If no one knows who you are," he said, "you're not a progressive."

Tzintzún Ramirez's campaign is unwilling to cede the viability mantle to Hegar. Noting she had a monthslong "head start on us," Tzintzún Ramirez campaign manager David Sanchez said the campaign is on its way to surpassing $1 million total raised by the end of this quarter. If the primary comes down to money, he added, "we're gonna be extremely competitive."

Despite the recent action centering on Hegar and Tzintzún Ramirez, polls show the primary remains wide open, with no candidate well known to Texas Democrats and large shares of primary voters unsure of whom they would vote for. A University of Texas/Texas Tribune Poll released last month found no candidate had higher than 24% name ID among Democratic voters, and 57% said they do not know who they will support or have an opinion yet.

The filing deadline was 6 p.m. Monday, and the field was anything but finalized in the days leading up to it. One of the candidates, Midland City Councilman John Love, dropped out three days before the deadline, saying he has "concluded that I lack the time and financial resources to compete as effectively as I would like." A new candidate, Houston nonprofit leader Annie Garcia, jumped in with days to spare, promising to bring the perspective of "one fed-up mama." And with a week until the deadline, O'Rourke supporters released a poll showing he would be the strongest candidate against Cornyn, reviving speculation about an 11th-hour run.

O'Rourke reiterated a few days later he would not run and never filed, but he still looms large over the race, both when it comes to policy — mandatory buybacks — and politics. About two hours before the filing deadline, Tzintzún Ramirez announced endorsements from 21 former staffers from O'Rourke's 2020 and 2018 campaigns — including 2018 campaign manager Jody Casey — seven of which are on Tzintzún Ramirez's staff.

O'Rourke said in September he would not consider endorsing in the primary, though he is not entirely receding from the fray. Hegar spoke with him Tuesday night, she revealed at a Tribune event the next morning, quickly making clear that he appears willing to help any candidate who wants it.

"I want to make sure that I'm not painting it like I have access to him or support for from him that other candidates don't," she said. "I think he's the type of servant leader that would answer the phone for anybody on the ticket and would give any of them advice."

In addition to swiping at Hegar over mandatory buybacks, Bell has questioned her commitment to the Democratic Party, suggesting in the same video that she has made a "recent entrance" into the party. It appeared to be a reference to her participation in the 2016 Republican primary, which she has explained as a protest vote against Donald Trump.

Tzintzún Ramirez, meanwhile, could tempt criticism with her acknowledgment last month that she narrowed her campaign's initial pledge against accepting all PAC money — a promise that O'Rourke famously adhered to — to just corporate PAC money. She said she dialed back the pledge after hearing from labor unions who wanted to have the option to give to her through their political arms.

Other candidates are largely staying out of the fray, driving messages that date to their campaign launches. West is continuing to stress his long record on Democratic issues since he first got to the Senate in 1993. "I've been there" is a common refrain of his stump speech — and so are reminders of his support from large majorities of his colleagues in the Senate and Texas House.

Edwards is continuing to lean on her experience in municipal government, while Bell is also pressing his experience — specifically his time in Congress that saw him file the ethics complaint that helped lead to the downfall of former U.S. House Majority Leader Tom DeLay, R-Sugar Land. Last month, Bell sought to further highlight that achievement when he released an anti-corruption plan after a Cornyn donor admitted to coordinating illegal campaign contributions in 2017.

As for the incumbent, there has been no shortage of colorful attacks from the Democrats as they seek to portray him as a toady of Senate Majority Leader Mitch McConnell and President Donald Trump. Hegar has referred to Cornyn as a "spineless, pantywaist, bootlicking ass-kisser," while Hernandez gave a closing statement Tuesday night that was similarly unvarnished.

"Going forward, I invite you to join me," she said, "so we can get bitch-ass Cornyn out of office."

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