Democratic presidential candidate Julián Castro responded to President Trump Donald John TrumpSteele Dossier sub-source was subject of FBI counterintelligence probe Pelosi slams Trump executive order on pre-existing conditions: It 'isn't worth the paper it's signed on' Trump 'no longer angry' at Romney because of Supreme Court stance MORE's attack Wednesday by saying he and his brother, Rep. Joaquin Castro Joaquin CastroPompeo accused of stumping for Trump ahead of election Florida Democrat asks FBI to investigate anti-Semitic, racist disinformation Hispanic Caucus members embark on 'virtual bus tour' with Biden campaign MORE (D-Texas), will keep fighting.

"Joaquin and I will keep fighting. The American people will fight every day for our nation, against your hate, your corruption, and your ego. And we’ll win. #AdiósTrump," Castro tweeted along with a video clip from the Democratic debate.

Joaquin and I will keep fighting. The American people will fight every day for our nation, against your hate, your corruption, and your ego. And we’ll win. #AdiósTrump https://t.co/nC0haWRydr pic.twitter.com/mMneHqXyT5 — Julián Castro (@JulianCastro) August 8, 2019

Trump lashed out at the Castros on Twitter on Wednesday night after the congressman tweeted names of prominent San Antonio-area Trump donors.

Trump initially misspelled Joaquin Castro's name. The deleted tweet was replaced with another echoing the same message.

"I don’t know who Joaquin Castro is other than the lesser brother of a failed presidential candidate (1%) who makes a fool of himself every time he opens his mouth. Joaquin is not the man that his brother is, but his brother, according to most, is not much. Keep fighting Joaquin!" Trump tweeted. ADVERTISEMENT

Members of Trump's campaign had criticized Joaquin Castro for sharing the list of donors.

Candidates are required to disclose names and employers of donors who give $200 or more in Federal Election Commission filings, which are publicly available online.

Trump's tweet came as he was leaving El Paso, Texas, after visiting victims of Saturday's mass shooting that killed 22 people.