The public can successfully pressure Senate Democrats to block the president’s plan to provide work permits to roughly five million illegals, says Sen. Jeff Sessions, the Senate’s leading advocate for pro-American immigration reform.

“You can stop this, we can stop it together,” Sessions said in a Tuesday speech. “The people control their government. Allowing any president to nullify law is a threat to the future of our Republic and the power of the people.”

Senate Democrats are vulnerable to public pressure because the president is expected to announce his executive amnesty only a few weeks before the November election, said a Hill aide. If the GOP pushes Democrats on the issue during September, they’ll convert the midterm election into a referendum on Obama’s immigration policies, he added.

Currently, Democrats are expected to lose several Senate seats in the election, but maybe not all of their six-seat majority. But if Obama follows through on his much-described plan to give work-permits to millions of illegal immigrants, then swing voters are likely to vote for GOP candidates, said the aide.

On Aug. 1, the House voted for a law that would simplify quick repatriation of recent border-crossers, and also end the president’s planned amnesty and his existing 2012 mini-amnesty for younger illegals, the so-called “Deferred Action for Childhood Arrivals” policy.

But the House bill won’t get anywhere unless Democratic senators pressure their leader, Sen. Harry Reid, to schedule a vote on the House bill. That’s where the public can have an impact, said Sessions.

“To every member of the public, red state or blue state or purple state, call your senator and ask them … if they support the House bill to block executive amnesty and if they will demand it receive a vote,” said Sessions, who says Americans’ wages would be raised by cutting the annual inflow of almost two million guest workers and immigrants.

“Let me share a message with my friends on the other side of the aisle,” Sessions said in his speech. “If you oppose executive actions, there is only one way to demonstrate it: support the House bill and demand it receive a vote in the Senate,” he said.

Sessions’ pitch is directed at voters, partly because polls show they’re increasingly worried about the impact of large-scale immigration on their jobs and wages, and are increasingly unhappy about Obama’s government-expanding policies.

“The president has simply decided — on his own, without Congress or legal authority — that the immigration laws protecting the jobs and wages of U.S. workers don’t exist anymore,” Sessions said. “The president has taken it upon himself to decide who can enter the U.S. and who can work in the U.S. — by the millions — regardless of what laws have been passed.”

A July poll of 1,044 Americans by The Associated Press and GfK Public Affairs showed that public approval of Obama’s immigration policies has slipped from 22 percent in May, to only 18 percent strong approval in July. Strong disapproval climbed from 43 percent to 57 percent, marking a 18-point shift away from Obama since May, said the AP/GfK poll.

But White House officials say the planned amnesty is popular, and that its popularity would make the president’s extraordinary move legitimate.

“I do think that as a practical matter, the president’s desire to act where Congress has failed is strengthened by the fact that there is such broad support all across the country for trying to impose common-sense solutions to a problem or a set of problems that everybody acknowledges exists,” said White House spokesman Josh Earnest said Monday.

So far, nearly all Democratic senators — including Reid — have stuck with Obama, despite the negative polls.

The only exception is West Virginia’s Sen. Joe Manchin. On Aug. 1, he voted with GOP senators to block Obama’s request for more than $1 billion to help many Central Americans illegal immigrants settle in the United States.

But Manchin — and all other Democratic senators — voted in June for an ambitious immigration bill that would have doubled the annual inflow of legal immigrants and guest-workers to roughly four million per year. That’s equal to the number of Americans who turn 18 each year.

That bill was publicly supported by 14 GOP senators, and was only strongly opposed by several GOP senators, including Sen. Sessions, Iowa Sen. Chuck Grassley and Texas Sen. Ted Cruz.

Sessions will have trouble rallying all or even most GOP senators to his cause, partly because major GOP donors strongly favor increased immigration.

However, the GOP establishment is making symbolic steps in Sessions’ direction.

On Tuesday, the Republican National Committee issued a press release slamming Obama’s immigration policies.

“It’s time for President Obama to wake-up from the alternate reality he’s living in. Threatening executive overreach as a political tool to turn out voters is not only flawed thinking but hurts vulnerable Democrats across the country and goes against overwhelming demands to secure our borders and strengthen interior enforcement,” said the statement by RNC Spokesperson Ali Pardo.

GOP senatorial candidates are also using immigration to club their Democratic rivals, despite many donors’ support for greater immigration. Would-be GOP Senators Tom Cotton in Arkansas, Scott Brown in New Hampshire, and Terri Lynn Land in Michigan, are using the issue.

“President Obama and Congressman Gary Peters have failed to enforce our immigration laws and secure our borders, resulting in lost Michigan jobs,” said a Wednesday statement from Land. “I support the rule of law and believe it is essential that we step up enforcement and make our immigration system fair.”

But at least one GOP senatorial candidate, Colorado’s Cory Gardner, voted against the House bill on Aug. 1, partly because of the growing number of Latino voters in the state.

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