Julian Castro was defiantly combative at the Democratic debate, and it paid off

• He may have been short on speaking time at the third Democratic debate, but former Housing and Urban Development Secretary Julián Castro used it to present himself as a younger, combative alternative to older Democratic presidential frontrunners like former Vice President Joe Biden.
• Castro used his first speaking opportunity to go after Biden, and President Barack Obama's former vice president was in his sights the entire night.
• Castro later blasted Biden's record on immigration, saying he was eager to embrace Obama's legacy without answering difficult questions about the extensive deportations of undocumented immigrants that took place during his presidency.
• Whether he's able to capitalize on his performance this time around remains to be seen, though the dynamic of the race is trending toward candidates promising drastic change.
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He may have been short on speaking time at the third Democratic debate, but former Housing and Urban Development Secretary Julián Castro used it wisely.

He presented himself as a younger, combative alternative to older Democratic presidential frontrunners like former Vice President Joe Biden at the debate in Houston on Thursday night.

Castro used his first speaking opportunity to go after Biden, and President Barack Obama's former vice president was in his sights the entire night. He took aim at his healthcare plan, a moderate alternative that shores up the Affordable Care Act with more federal subsidies - and said it didn't go far enough in ensuring affordable coverage for Americans.

It was only the first salvo. He pointedly questioned Biden's memory, saying, "Are you forgetting what you said just two minutes ago?," a line that drew him some criticism.

Read more: 'I'm fulfilling the legacy of Barack Obama and you're not': Julian Castro comes out swinging at Biden over healthcare in Democratic debate

Castro positioned himself as the candidate who would best carry on the Obama legacy, telling Biden: "I'm fulfilling the legacy of Barack Obama and you're not."

He later blasted Biden's record on immigration, saying he was eager to embrace Obama's legacy without answering difficult questions about the extensive deportations of undocumented immigrants that took place during his presidency.

Castro, however, wasn't alone in going after at Biden. The former vice president had a target on his back throughout the night, and he struggled at times to swing back at rivals such as Sens. Bernie Sanders and Elizabeth Warren.

But Castro needed a strong debate performance, given that he's still languishing toward the bottom of most polls. Castro enjoyed a strong performance at the June Democratic primary debate as well, though he failed to turn it into a major polling bump. It did, however, lead to a substantial uptick in his fundraising and increased attention.

Whether he's able to capitalize on it this time around remains to be seen, though the dynamic of the race is trending toward candidates promising drastic change to President Donald Trump's Washington.

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