During a private fundraiser in San Antonio, former Vice President Joe Biden couldn’t help but talk about Julián Castro, one of his Democratic rivals for the White House.

Biden didn’t mention any of the other Democrats in the presidential race by name during his speech to about 125 people, but when it came to Castro, Biden told the audience that he is a “great former mayor.”

Biden said for him, it was even awkward being in Castro’s hometown raising money. Castro was mayor of San Antonio from 2009 to 2014.

“I almost feel guilty about being in this town,” Biden said.

He said he told his staff to reach out to the Castro campaign before the event to just make sure they knew he was going to be in the area. Biden told the crowd there are still basic protocols that political candidates have to observe, and that is what he was trying to do.

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Those comments come months after some spirited debate moments over the last six months, including one exchange in which some political commentators accused Castro of attacking Biden about his age — a charge Castro denied.

As for the rest of the field, Biden told the crowd that “generally we’re all on the same page” when it comes to wanting affordable, universal health care and improving education. He said there are disagreements on the details of how to do it, but the same fundamental desire is there.

Besides the fundraiser, Biden earlier held a public rally Friday at La Villita. It was his first visit to San Antonio since he announced his campaign for the White House back in April.

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Polls show Biden has a commanding lead in Texas. A CNN poll released last week showed Biden with a 20 percentage point lead over U.S. Sen. Bernie Sanders. Castro was 32 percentage points behind Biden and tied with New York entrepreneur Andrew Yang for sixth place with 3 percent support.

The Texas Presidential Primary is on March 3. Early voting for the primary starts Feb. 18.