Ken Paxton, the Republican legal professional basic of Texas, pleaded not responsible to fees of corruption and bribery Tuesday on the opening day of his impeachment trial earlier than the State Senate, the primary such continuing for a statewide officer in additional than a century.

Mr. Paxton, a third-term incumbent championed by hard-core conservatives and former President Donald J. Trump, is going through trial on 16 articles of impeachment associated to accusations, primarily by his former high deputies who grew to become whistle-blowers, that he had abused his workplace for the good thing about himself and an Austin actual property investor who was stated to have assisted Mr. Paxton with house renovations and an extramarital affair.

“Those allegations are flat-out false,” his lead counsel, Tony Buzbee, stated, talking for Mr. Paxton. “The attorney general pleads not guilty.”

The trial has introduced a novel take a look at for Republican leaders and lawmakers within the Texas Capitol, the place the social gathering exerts overwhelming management, and for the longer term route of the social gathering extra broadly. Even earlier than the proceedings started, some Republican lawmakers have been going through a public pressure campaign backed by rich conservative donors, reflecting the affect Mr. Paxton wields on account of main conservative authorized fights on points reminiscent of immigration, abortion and transgender policies.

Mr. Paxton has sought to strongly align himself with Mr. Trump. But his scenario has so far differed from that of the previous president: in Texas, Republican politicians are those main the impeachment towards him.

A majority of Republicans within the Texas House joined in a 121-to-23 vote in May to question Mr. Paxton. On Tuesday, a majority of Republican Senators started the proceedings by voting to maneuver ahead with the trial, dispatching by broad margins a number of makes an attempt by Mr. Paxton’s attorneys to have the whole case dismissed.

When Mr. Paxton’s attorneys put forth a collection of unsuccessful motions to dismiss the case, all however one failed by a vote of greater than two-thirds of the senators current.

The unsuccessful maneuvering supplied early hints into how the trial would possibly take form: Mr. Paxton had the assist of a core of six senators, who voted in favor of every of his attorneys’ motions. But a stable majority of Republicans don’t seem to view the trial as a “sham,” as a few of his supporters have known as it.

Among the state senators seated principally in silence was Mr. Paxton’s spouse, Angela Paxton. According to the foundations, she can be counted as current for the needs of the two-thirds majority wanted however barred from voting or becoming a member of in any deliberations.

As the votes got here down towards his attorneys, Mr. Paxton sat in silence at a desk to the entrance of the towering chamber, its seats organized to resemble a courtroom. Similarly subdued have been the gathered spectators. More than 100 individuals, principally supporters of Mr. Paxton, fanned out throughout the second-floor gallery with shirts proclaiming themselves to be “RINO” hunters — referring to “Republicans in name only” — or supporters of the hard-core conservative group, the True Texas Project.

A large number of the Senate gallery’s 497 seats were empty.

“We thought we’d have more people here,” said Jane Anne Sellars from Frisco in North Texas, a 69-year-old supporter of Mr. Paxton and retired municipal government official. “We were looking for more red.”

Alicia Davis drove five hours to Austin from the East Texas city of Jasper on Monday and was among the first to line up at the Texas Capitol before daybreak on Tuesday morning. “It’s an embarrassment,” she said of the impeachment, which she regarded as unwarranted. Ms. Davis, who is a Republican candidate challenging the Texas House speaker, Dade Phelan, said that she expected the trial would be “a mess.”

A total of 20 articles of impeachment were approved by the Texas House. But the Senate opted to hold off on considering four articles related to Mr. Paxton’s 2015 indictment for securities fraud; those articles could be part of a future proceeding or dismissed at the end of the trial.

Mr. Paxton’s lawyers did succeed in one key motion: preventing their client from being compelled to testify. The lieutenant governor, Dan Patrick, who is acting as a judge in the impeachment trial, ruled that Mr. Paxton could not be forced to testify.

After a lunch break, Mr. Paxton, who has been suspended from office since the House vote, was no longer present in the chamber, a fact that drew immediate notice and an objection from Rusty Hardin, a lawyer for the House Board of Managers, a group of lawmakers who are overseeing the impeachment. Mr. Patrick decided the rules did not require Mr. Paxton to be there.

Mr. Paxton is accused of using his office to benefit the Austin real estate developer Nate Paul, who donated $25,000 to his campaign and, according to the articles of impeachment, paid for his home renovations and helped him engage in an extramarital affair.

“He is not fit to be the attorney general of Texas,” said Representative Andrew Murr, a Republican from rural West Texas, who gave the opening statement for the House impeachment managers. He spoke for about 30 minutes, half the time allotted under the rules.

Tony Buzbee, a lawyer for Mr. Paxton, went through the accusations against Mr. Paxton in far greater detail, providing rebuttals to many of the pieces of evidence and suggesting that it had been the whistle-blowers who acted improperly. He presented the trial as having been born of political retribution by an “establishment” that had been unable to defeat Mr. Paxton at the polls.

“What can be less democratic than 30 people deciding who serves as attorney general of Texas?” said Mr. Buzbee, who successfully represented former Gov. Rick Perry when he was indicted on abuse of power allegations in 2014.

The first witness for the prosecution, Jeff Mateer, was one of the whistle-blowers whose accusations landed Mr. Paxton in political peril. Mr. Mateer, who served for a time as a first assistant attorney general under Mr. Paxton, presented his conservative legal credentials and those of the others who spoke about their bosses’ actions.

“Are you a RINO?” Mr. Mateer was asked by Mr. Hardin.

He said no, emphatically. He described himself as an evangelical Christian. “I was nominated by President Trump to be a federal judge,” Mr. Mateer said, though he was not confirmed.

The trial was expected to last as long as a month. Each side would be given a total of 24 hours for each side to present its evidence and witnesses. A conviction on any of the articles by two-thirds of the Senate, made up of 19 Republicans and 12 Democrats, would be enough to remove him from office. The senators could also vote to bar him from running again.

Among Mr. Paxton’s supporters within the gallery on Tuesday was Steve Hotze, a far-right Republican donor and activist in Houston who has backed conservative causes, together with an investigation he funded upfront of the 2020 presidential election that resulted in an assault and, later, indictments. “I came here because there’s nothing more important than the power of your personal presence,” he said. “We already know there are six votes for Paxton — all he needs are five more.”

But, he added, a conviction on any of the articles of impeachment would mean removal of Mr. Paxton from office. “It’s a high hill to climb,” Mr. Hotze said. “It’s a high hill for him.”