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An Iowa immigration activist says he wants Republican candidates to show up to the Iowa Freedom Summit that Rep. Steve King has organized for this weekend and champion immigration reform.

"Not going is the easy way out," Matt Hildreth, an activist based in Iowa who works for pro-immigration reform group America's Voice, said Thursday in a phone call with other immigration organizers.

Erika Andiola, codirector of DRM Action Coalition said immigration reform backers need to not only hold accountable elected officials but "make sure those who are running for the presidency are also being held accountable for what they are saying."

King, R-Iowa, has been a controversial figure with his comments about immigrants regarded as insults and slurs in the Latino community. Most recently, he referredto a young immigrant who sat with first lady Michelle Obama during the State of the Union as a "deportable" in a tweet and didn't use her name, which caused immediate backlash among many in the Latino and immigrant community.

The summit scheduled for Saturday is expected to draw some of the 2016 presidential hopefuls although former Fla. Gov. Jeb Bush has said he's not attending. Sens. Marco Rubio, R-Fla. and Rand Paul, R-Ky., and failed 2012 GOP presidential nominee Mitt Romney are not on the summit's list of confirmed attendees.

Young immigrants who arrived or stayed in the U.S. illegally as children and often refer to themselves as DREAMERS plan activities around the event, including confronting potential candidates to ask them where they stand on immigration reform and the president's executive action.

In advance of the summit, Iowa activists ran an ad in the Des Moines Register to show immigration reform has support in the state. The ad was addressed to King and not to the potential 2016 candidates. It took a largely softer tone by comparison to comments by King.

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"The last thing we want is for candidates to stop coming to Iowa," Hildreth said. "We fear candidates will stop coming because they want to avoid Steve King altogether."

In a phone call with reporters Thursday, some of the activists acknowledged that they are unlikely to change King's views on immigration but also said he's had influence on the GOP and the direction its headed on immigration.

Harold Heie, board member of Sioux County, Iowa CASA and organizer of the ad that had 125 signatures, said he thinks King is on the verge of marginalizing himself within his own party.

A spokeswoman for King could not be immediately reached by phone or email.