Hillary Rodham Clinton’s fighting words on immigration this week, designed in part to provoke Republicans into a reactionary counterattack, instead drew an unusual early response from several top-tier GOP presidential candidates: silence.

Two days after Clinton vowed to expand on President Obama’s executive actions to shield up to 5 million undocumented immigrants from deportation, Wisconsin Gov. Scott Walker was one of the only leading Republican 2016 contenders to strike back, calling it a “full embrace of amnesty” that is “unfair to hard-working Americans.”

By contrast, former Florida governor Jeb Bush, Sen. Marco Rubio (Fla.), Sen. Rand Paul (Ky.) and New Jersey Gov. Chris Christie did not weigh in publicly on the remarks Clinton made Tuesday at a campaign stop in Las Vegas. Sen. Ted Cruz (Tex.), one of Obama’s most vocal critics on immigration, waited until Wednesday evening to respond on Facebook, writing that Clinton wants to “continue and expand President Obama’s illegal amnesty” and “continue the lawlessness that is dividing our country.”

Former Arkansas governor Mike Huckabee told MSNBC on Wednesday that Clinton was wrong, saying the country needs to focus on border security first.

Former U.S. senator and secretary of state Hillary Clinton announced that she’s running for president in 2016. Here's the Democrat’s take on women’s rights, Benghazi and more, in her own words. (Julie Percha/The Washington Post)

The relatively subdued GOP reaction illustrated a dilemma for a Republican Party still wrestling with the hot-button issue of immigration three years after Obama routed Mitt Romney behind overwhelming support from Latinos and Asian Americans.

Although virtually all of the Republican hopefuls have denounced Obama’s executive actions, which are wildly unpopular with the GOP’s conservative base, they recognize that staking out a hard-line immigration position probably would harm their status with two of the fastest-growing subsets of the electorate. In 2012, Romney advocated “self-deportation” for illegal immigrants, earning him scorn from Latino groups.

“The waters are treacherous, which explains the muted response,” said William J. Bennett, education secretary under President Ronald Reagan and now a talk-radio host. “Not one of the campaigns, with the exception of Jeb Bush, have full clarity on where they want to go, and people are doing a lot of moving.”

Fergus Cullen, a former chairman of the Republican Party in New Hampshire, home to the first-in-the-nation primary, was even blunter, blaming his compatriots for not putting the issue of immigration reform behind them. House Republicans last summer refused to vote on a bipartisan border control bill, approved by the Senate, that included a 13-year path to citizenship for illegal immigrants.

“Republicans’ intransigence has created an obvious opportunity for Hillary to rip off our arms and beat us with the bloody ends,” Cullen said. “She’s expertly exploiting our party’s internal problems.”

Last year, Obama delayed his executive actions until after the midterm elections at the behest of jittery Senate Democrats, only to see the party lose control of the chamber anyway. Now, Clinton’s enthusiastic embrace of Obama’s immigration actions so early in the election cycle has been an unequivocal sign that Democrats, once wary of an issue former Obama chief of staff Rahm Emanuel has called the “third rail of American politics,” may believe that immigration is a golden ticket to electoral-college success.

During her appearance in Las Vegas — where a growing Latino population helped power Obama to a 2012 victory in Nevada — Clinton again backed a path to citizenship and said she would potentially go further than the president to protect immigrants from deportation until Congress reforms border control laws. She goaded Republicans, saying they are supporting “second-class status” for illegal immigrants.

Her pitch to the left was so emphatic that White House aides, who had said Obama’s executive actions in November represented the limit of his legal authority, were compelled to defend him Wednesday for not going further.

“The president’s views have not changed,” White House press secretary Josh Earnest said during his daily briefing when asked whether Obama believed he could do more in light of Clinton’s announcement. Asked whether her pledge to expand the deportation relief would hold up legally, Earnest added, “That’s something for a future president and future courts to decide.”

Public polling has shown split views on Obama’s immigration actions. In a Washington Post-ABC News poll in January, 41 percent said the actions should go forward and 56 percent said they should be blocked. But support among Hispanics for the president’s initiatives was 80 percent, compared with 28 percent among whites.

Other surveys have showed higher levels of overall support for allowing illegal immigrants to remain in the country and work and to eventually apply for citizenship.

That has presented difficulties for Republican contenders who have struggled to articulate a clear vision on immigration reform.

“One of the biggest challenges we’ve had with Hispanic voters is that we’re defined by what we’re against rather than what we’re for,” said Kevin Madden, a former Romney adviser. “We created a lot of problems for ourselves in 2012 when we had an immigration platform that was defined by ‘self-deportation’ and expected to win their support.”

Bush, who is the former governor of a state with a large Hispanic population and whose wife is Mexican American, has endorsed a path to legal status for the undocumented, but he has pledged to overturn Obama’s executive actions.

Rubio, the son of Cuban immigrants, helped negotiate the Senate’s immigration bill last year but backed away after House conservatives killed it. And Walker has said his views on immigration have changed since he previously voiced support for a citizenship plan.

In a statement, Walker said Wednesday that Clinton’s position “is unfair to hardworking Americans and all immigrants who followed the law to achieve the rights and privileges afforded to U.S. citizens. And by supporting the president’s lawless executive action, Hillary Clinton once again believes she’s above the law.”

Immigration advocates have delighted in Clinton’s proactive move, noting that it was perhaps most vexing for Bush, who has sought to position himself as slightly more moderate among the GOP field on immigration.

“He has been going on two years of going back and forth on the question of citizenship: What’s doable? What’s viable in his party?” said Marshall Fitz, vice president of immigration policy at the left-leaning Center for American Progress. “But he hasn’t formally stuck to his guns on what is the right thing to do, and she called him out on it.”

Republican political strategists, trying to look for an upside, suggested that as Clinton shifts to the left, her candidacy risks seeming emblematic of a third Obama term.

“She’s boxing them in a little, but she’s also linking herself more significantly to Obama,” said Ed Rollins, a veteran Republican consultant. “If his approval ratings are above 50 percent next year, it’s smart. If they’re below 50 percent, she won’t do well.”

Peyton M. Craighill, Anne Gearan, Jenna Johnson, Sean Sullivan and Katie Zezima contributed to this report.