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Latino conservatives who oppose Donald Trump are watching his streak of victories with concern over the impact on Latinos as well as the future of the Republican Party’s relationship with the community.

Alfonso Aguilar, a former official of the George W. Bush administration and executive director of the Latino Partnership for Conservative Principles, will be among a coalition of conservative and GOP Latino leaders who are planning to meet in Houston on Friday.

“We’re going to discuss how to proceed and whom we should endorse, if we endorse anyone,” Aguilar, who supported Jeb Bush’s campaign and now is backing Marco Rubio, told Fox News Latino.

For his part, Aguilar is firmly opposed to Trump and says that if he winds up being the GOP nominee, he will urge Latinos to vote but leave the ballot blank.

“That will send a message,” Aguilar said.

Last year, alarmed by Trump’s hard line stance on immigration and comments about immigrants that many Latinos called offensive, Aguilar and other conservative Latino leaders met in Nevada and later held a press conference warning Republican Party leaders that they needed to push back harder against the harsh rhetoric.

Part of their message was that the GOP would undo any gains it had made among Latinos since the bruising defeat in 2012 of the party’s presidential nominee, Mitt Romney, to Pres. Barack Obama, whom Hispanics backed by a 71-27 percent.

And they believe that a President Trump would be detrimental to Latinos.

Aguilar thinks Rubio is the best GOP candidate in the race. Rubio has emerged as the leading so-called "establishment" candidate. Many party leaders believe Rubio has the best chance of winning a general election against Democrats Hillary Clinton or Bernie Sanders.

“He’s a formidable candidate, and the Clinton people are afraid of him,” Aguilar said of Rubio.

“He’s a good conservative. He energizes the base, but he will be very competitive as far as Latino voters – because he is young, smart and constructive on immigration.”

Al Cardenas, one of the nation’s most influential conservatives and a senior adviser to Jeb Bush’s presidential campaign, told FNL that it may be nearly impossible at this point to stop Trump.

“I’m kind of off the presidential political grid for a while,” Cardenas said. “The way this thing looks to me, it could be over sooner than we know. While Marco Rubio and Ted Cruz still remain in the race, neither has a chance to beat Donald Trump.”

The only way that one of them could beat Trump, who has won the last three state contests, Cardenas said, would be if either Cruz or Rubio were to bow out in the next two weeks.

“One has to drop out and support the other,” Cardenas said, noting that they have gotten more than 20 percent of the vote each, making it easier for Trump to be the top vote-getter.

“You can’t just sit back and hope that Trump implodes,” Cardenas said, “because people have been waiting for that for a very long time now.”

On Super Tuesday, there will be 11 states holding primaries, and if Trump gets a majority of those, Cardenas said, he would be the de facto GOP nominee.

“Cruz or Rubio have to start winning states,” Cardenas said. “It’s not enough to come in second and third. If Trump gets, say, 5 of 11 states next week, Cruz or Rubio would have to get the rest.”

“We’ll probably have the nominee by March 15,” he said.

Daniel Garza, the executive director of LIBRE, a conservative Latino-outreach and free-market advocacy organization financed to a large extend by the Koch brothers, says Trump’s Latino support in Nevada should not be dismissed.

“Obviously, there’s all this [criticism] about sample size” of Latinos in the Nevada caucus entrance polls, Garza said. “But it obviously shows that there are Latinos who support him, and who are not one-issue voters. Many Latinos support enhanced border security.”

“And of course, Trump’s charisma is very appealing,” Garza said. “Trump is capturing the angst that many Americans – Latinos and not – have about the economy.”

Garza said that LIBRE is not working for or against any single candidate at this stage.

Instead, the group – which has field staff in many battleground states, where they hold workshops on numerous topics – wants to educate Latinos about policy issues, he said.

“Trump hasn’t really defined where he stands on a lot of spending and entitlement reform issues,” Garza said. “He’s proposing what would be the largest tax increase in our history, and we’ve made our [opposition] clear on where he stands on immigration.”

“[His positions] are of concern to us and should be to a lot of Latinos,” he said.

“Our plan going forward is to focus on policy and to educate Latinos, and that especially, when they [make a choice] on Election Day, that they choose in a way that is informed.”