Kris Kobach, the polarizing former Kansas secretary of state who once headed President Trump’s short-lived election integrity commission, on Monday launched a Republican bid for Senate, pledging to “lead the charge” against illegal immigration and socialism.

Kobach’s bid to succeed retiring Sen. Pat Roberts (R) immediately stoked GOP fears that his candidacy, coming less than a year after a failed gubernatorial campaign, could imperil a crucial seat in a state that hasn’t sent a Democrat to the Senate since the Great Depression.

Speaking at an event in Leavenworth, Kobach sounded a defiant tone in pledging loyalty to President Trump over the wishes of “establishment” Republicans who have sought to keep him out of the race.

“This is not a time for a quiet senator. It’s not a time for a senator who wants to make everybody happy and doesn’t want to take a stand,” said Kobach, standing in front of a “Build The Wall” banner beside his wife and children. “The Washington establishment wants a tool — a quiet, useful tool — who will keep the status quo going. Well, guess what? The Washington establishment is not going to get what they want.”

Last year, Kobach lost the governor’s race by five percentage points to Democrat Laura Kelly in heavily Republican Kansas — with Trump’s hearty endorsement — after a campaign that was criticized for its fundraising struggles and disorganization.

His entrance into the Senate race was immediately panned by the National Republican Senatorial Committee.

“Just last year Kris Kobach ran and lost to a Democrat,” said NRSC spokeswoman Joanna Rodriguez. “Now, he wants to do the same and simultaneously put President Trump’s presidency and Senate majority at risk. We know Kansans won’t let that happen and we look forward to watching the Republican candidate they do choose win next fall.”

There were immediate signs that Kobach, 53, might not have overcome his previous organizational hiccups: His campaign filed papers with the Federal Election Commission that misspelled his name as “Chris Kobach.” The filing was later updated.

During his remarks, Kobach cast himself as a steadfast ally of Trump, saying, “I will help the president make America great again.” He described speaking to Trump as recently as Thursday “on the subject of illegal immigration,” although it remains a question whether his run has Trump’s blessing.

“There really hasn’t been anyone in the Senate who’s been pushing his agenda,” Kobach said. “The Senate has come along kicking and screaming in many instances, not leading. And so if I am elected, God willing, to this Senate seat, I will be leading the charge for President Trump in the United States Senate.”

Kobach recounted his work as general counsel to a group, We Build the Wall, that raises private money to build barriers at the U.S.-Mexico border and pledged that he would help Trump achieve his long-promised goal of a border wall. The group has raised more than $20 million but its early efforts to build a barrier in southeastern New Mexico have done little to address the larger issues at the border.

“We will build the wall faster and better if I’m elected,” Kobach said.

He also touted his efforts to advise Trump on adding a controversial citizenship question to the 2020 Census and warned of what he called a socialist agenda being pushed by Democrats in Washington.

“America must never become a socialist country,” Kobach said. “You don’t build a country on free stuff. You build it on freedom, and that’s what made America great.”

Senate Majority Leader Mitch McConnell (Ky.) and other Republican leaders have tried to court Secretary of State Mike Pompeo, a former Kansas congressman, to run to succeed Roberts, who announced in January that he would not seek another term.

Earlier this year, Pompeo ruled out a Senate bid, saying he wanted “to be the secretary of state as long as President Trump gives me the opportunity to serve as America’s senior diplomat” — though some Republican strategists believe that he might still be persuadable.

Several other Republicans are eyeing the Senate race, including U.S. Rep. Roger Marshall, Kansas State Treasurer Jake LaTurner and former Kansas City Chiefs football player Dave Lindstrom.

Two Democrats, former congresswoman Nancy Boyda and former U.S. attorney Barry Grissom, have entered the race.

A spokesman for the Senate Leadership Fund, a GOP super PAC with close ties to McConnell, said Monday that “Kansas Republicans deserve a nominee who can win” without specifically mentioning Kobach.

“While we haven’t made any decisions about our engagement, after last year’s gubernatorial result, it is imperative Republicans put our best foot forward in Kansas,” said the spokesman, Jack Pandol.

In January 2018, Trump announced that he was disbanding the Presidential Advisory Commission on Election Integrity, which had been nominally chaired by Vice President Pence and led by Kobach, who aggressively sought to prosecute alleged voter fraud in Kansas during his tenure as secretary of state.

The 11-member commission met only twice amid lawsuits seeking to curb its authority and claims by Democrats that it was stacked to recommend voting restrictions favorable to the president’s party.

Trump had created the commission in response to his claim, for which he provided no proof, that he lost the popular vote to Democrat Hillary Clinton in 2016 because of millions of illegally cast ballots.

Kobach more recently has been involved in the controversy over the administration’s efforts to add a citizenship question to the 2020 Census.

Kobach met with Trump and some top aides to discuss the issue and sent a note to Commerce Secretary Wilbur Ross in July 2017 complaining that the lack of such a question “leads to the problem that aliens who do not actually ‘reside’ in the United States are still counted for congressional apportionment purposes.”

When summoned before a House panel last month, Kobach refused to answer several questions after the White House told him not to discuss his conversations with the president.

As secretary of state, Kobach moved to require Kansas voters to show proof of citizenship when registering to vote — a law that was overturned last year after a court found no credible evidence to support the claims of massive voter fraud underpinning it. The federal judge in that case sanctioned Kobach for “contemptuous behavior” and ordered him to pay more than $26,000 in attorney fees and expenses.