WASHINGTON — When President Trump suggested foreign-born Americans should “go back” to the countries they were born in if they do not like it here, he may not have realized that his entreaty could have been addressed to 5 percent of Congress.

In all, 29 members of the House and Senate were born abroad, about half of them to parents serving in the military or working overseas. They include a doctor born in Mexico (Representative Raul Ruiz, Democrat of California); a lawyer born in Japan (Senator Mazie K. Hirono, Democrat of Hawaii); a women’s rights advocate born in India (Representative Pramila Jayapal, Democrat of Washington); and a real estate developer born in an Army hospital in France (Representative Mark Meadows, Republican of North Carolina).

Republicans like Mr. Meadows and Representative David Rouzer, also of North Carolina and born in an Army hospital in West Germany, have mostly stood by the president, who aimed his remarks at four progressive House Democratic women of color, only one of whom was born outside the United States.

“No, I don’t think it’s racist,” Mr. Rouzer said.

But to others, Mr. Trump’s words — which he repeated on Tuesday — hit home in a deeply personal way, resurfacing painful memories of past racial taunts. Those feelings were reflected in the resolution the House took up Tuesday condemning Mr. Trump. Immigrant Democrats led the effort on the House floor.