Hialeah, Florida (CNN) During his presidential campaign announcement, Florida Sen. Marco Rubio came out swinging with a punch list that included the popular Republican mantra to "repeal and replace Obamacare." But the Department of Health and Human Services had already thrown a punch of its own earlier in April.

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HHS released its updated list of enrollments by zip code and it turns out the top 15 are in Rubio's backyard - Miami-Dade and Broward counties. In fact, the second highest zip code in the country is 33126, which lies just blocks from the City of West Miami, where Rubio got his political start. That area saw 11,222 people sign-up for the healthcare benefits, in the enrollment period ending in February.

That's roughly 4,000 less than the top Obamacare zip code in the United States, 33012, which is in the heart of Hialeah, a Republican stronghold.

In the last presidential election, which was dominated with rhetoric about the Affordable Care Act, the so-called "City of Progress" voted roughly 58% to 42% in favor of Mitt Romney. It's a red island in a sea of blue, when you take into account that surrounding Miami-Dade County has gone for a Democratic presidential nominee in every election since 1992.

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