Rep. Steve King (R-Iowa) pushed back Friday on the notion the GOP was doing poorly among Hispanic voters with a tweet knocking Housing and Urban Development Secretary Julian Castro.

King tweeted Friday morning:

What does Julian Castro know? Does he know that I'm as Hispanic and Latino as he? pic.twitter.com/CYmNIdyqLW — Steve King (@SteveKingIA) July 17, 2015

The hard-line conservative lawmaker made the remark shortly after another tweet calling to "restore profiling by law enforcement" and "abolish cultural relativism & gun free zones."

King said that Mohammad Youssuf Abdulazeez, the gunman in the Tennessee shooting the previous day that left four Marines dead, "fit exact profile of Islamic Jihad."

Castro, the former Democratic mayor of San Antonio who has served as HUD secretary since last summer, is rumored to be a top running mate candidate for Hillary Clinton Hillary Diane Rodham ClintonREAD: Cohen testimony alleges Trump knew Stone talked with WikiLeaks about DNC emails County GOP in Minnesota shares image comparing Sanders to Hitler Holder: 'Time to make the Electoral College a vestige of the past' MORE, the Democratic frontrunner.

Republicans have sought during recent election cycles to make inroads among Hispanics, an increasingly important voting group that went overwhelmingly for President Obama in 2012.

During an interview in May, Castro said he was "flattered" by the Clinton rumors but said he was "not holding my breath" and focused on his work within the Obama administration.