Democratic presidential candidate Bernie Sanders is significantly increasing his focus on Texas with a little over a month until the state's primary.

On Tuesday, his campaign unveiled plans for a $2.5 million TV ad buy across Texas and California — another delegate-rich Super Tuesday state — and told The Texas Tribune that it has staffed up here with five regional field directors. The campaign is also dispatching a top surrogate — national co-chair Nina Turner — to Houston this week.

While Sanders has maintained a devoted following in Texas since his 2016 campaign, other top-tier candidates have so far received more attention ahead of the March 3 primary. Elizabeth Warren was the earliest to begin formally organizing here, Joe Biden has amassed a long endorsement list, and Michael Bloomberg is promising an unprecedented effort in the state that will continue through the general election.

Sanders' relatively low profile in the Texas primary conversation appears to be over. The ad buy makes him the first known candidate to reserve major TV time in the state beside billionaire rivals Michael Bloomberg and Tom Steyer. In Texas, the campaign will air two 30-second spots, one that touts Sanders as a "fighter" and another that pitches his economic platform.

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The new regional field directors are Katy Bravenac (San Antonio and El Paso), Sierra White (Houston), Jose Jimenez (Rio Grande Valley), PJ Martinez (Dallas-Fort Worth) and Trumaine Smith (Austin). They will work under the campaign's Texas state field director, Chris Chu de León, who already has a three-person team in Texas consisting of a full-time campus organizer and two other organizers.

Chu de León and his team embarked last month on a "Turnout Texas" organizing tour that includes over 70 stops across the state.

Sanders has not visited Texas since September, though candidate trips to the state in general have tapered off over the past couple months as the field has narrowed and they zero in on the earlier-voting states. The exception has been Bloomberg, who is skipping the first few states and is set Wednesday to make his fourth swing through Texas in less than two months.

Both Bloomberg and Sanders' co-chair Turner are set to speak this week at the National Newspaper Publishers Association Future of Black America Symposium in Houston. While in Houston, Turner will also meet with local elected officials, community leaders and activists, according to the Sanders campaign.