WASHINGTON — The ghost of Howard H. Baker Jr., the Republican senator from Tennessee who turned against Richard M. Nixon during Watergate, is hovering over Senator Lamar Alexander.
Mr. Alexander, a third-term Republican from Tennessee who is retiring at the end of this year, has said that no one outside his family has had more influence on him than Mr. Baker, the former Senate majority leader who is remembered for the penetrating question he posed as Nixon stared down impeachment: “What did the president know, and when did he know it?”
Now Mr. Alexander may hold in his hands the fate of another Republican president who is facing removal from office. He is one of four Republican moderates who have expressed openness to bringing witnesses into President Trump’s impeachment trial — and the only one who is not running for re-election and arguably has nothing to lose.
Yet as the Senate heads toward a vote on the matter, Mr. Alexander — who has broken with Mr. Trump over trade, the border wall and health care — does not appear ready for a Howard Baker moment. He has said he will make a decision about witnesses after Mr. Trump’s team presents its defense and senators have an opportunity to ask questions, but he does not sound eager to defect.
“As the House managers have said many times, they’ve presented us with a mountain of overwhelming evidence,” he told reporters in the Capitol on Friday. “So we have a lot to consider already.”
Mr. Alexander’s caution suggests what Republicans in Tennessee and around the country already know: that the Howard Baker wing of their party, the one populated by moderate-leaning conservatives willing to reach across the political aisle, is virtually extinct. Bob Corker, another Tennessee Republican, learned as much when he spoke out against Mr. Trump and then felt compelled to retire in 2018 from the Senate. So did Jeff Flake, the former Republican senator from Arizona, who watched some of Mr. Trump’s trial from the Senate gallery this week.
“As a Republican, it pains me when I see Republicans, House Republicans, try to maintain that the president did no wrong, that this is somehow normal. It’s not,” Mr. Flake told reporters, though he said he was not sure he would vote to convict Mr. Trump.
That kind of talk is absent among Republicans in the Senate these days, even from members like Mr. Alexander, who in 2016 made clear that “Trump was not his first choice for president,” as his hometown newspaper, The Nashville Tennessean reported. But if Mr. Alexander has issues with the president, he tends to raise them quietly, people who know him say.
There is little question that Mr. Alexander will vote to acquit Mr. Trump. He has called the House impeachment inquiry “a circus,” and said Democrats made a “mistake” in charging Mr. Trump with high crimes and misdemeanors for pressuring Ukraine to investigate his political rivals. But he was among four Senate Republicans — along with Susan Collins of Maine, Lisa Murkowski of Alaska and Mitt Romney of Utah — who pressed Senator Mitch McConnell, the majority leader, to allow a vote on whether to subpoena witnesses and seek new documents.
The White House has regarded Mr. Alexander — who does not have a close relationship with Mr. Trump — as a wild card in the proceeding.
Democrats, who control 47 votes in the Senate, would need four Republicans to join them to expand the scope of the trial, but so far only two — Ms. Collins and Mr. Romney — seem to be leaning into the idea.
And Mr. McConnell, Republican of Kentucky, who is close with Mr. Alexander, is determined to hold Republicans together to block it. The two men met in Washington in 1969, when Mr. Alexander was a young aide in Nixon’s White House and Mr. McConnell a legislative assistant on Capitol Hill. It was Mr. Baker who introduced them.
“I seek his counsel on a weekly basis on a whole variety of issues,” Mr. McConnell said in a brief statement. “He’s my closest friend in the Senate.”
Mr. McConnell has sometimes used Mr. Alexander as a conduit to Democrats, particularly to Harry Reid, the former senator from Nevada, when he was minority leader. Mr. Reid and Mr. McConnell did not get along, so Mr. Alexander — who had been in Republican leadership but stepped away to focus more on legislation — served as an “honest broker” between the two, said Jim Manley, a former aide to Mr. Reid.
But Mr. Manley said Mr. Alexander “still toed the party line.”
When Mr. McConnell put forth a resolution setting up a speedy timetable for the impeachment trial, some Republicans balked and Democrats objected. But Mr. Alexander issued a statement praising the rules.
People close to Mr. Alexander say they have no idea whether he will vote to allow witnesses — and that he may not know yet himself. Should he do so, he would be a “pariah” in the state, said one conservative activist in Tennessee, who requested anonymity to speak candidly about a sitting senator.
His seeming reluctance to speak out against Mr. Trump has disappointed some of Mr. Alexander’s admirers. Richard L. Clinton, a professor emeritus of political science at Oregon State University who was in the same fraternity as Mr. Alexander at Vanderbilt more than 60 years ago, posted an open letter this week to the senator on the web site of the progressive newsletter Common Dreams.
Under the headline “Where is Your Courage and Decency?” Mr. Clinton wrote that he remembered Mr. Alexander as “an exceptionally intelligent, hard-working, and trustworthy young man,” and was thus “perplexed” by his silence. He urged the senator to renounce Mr. Trump and “employ his considerable abilities and unique position to begin making our country whole again.”
But aggravating others is not Mr. Alexander’s style; he appears to see himself as more of a bridge builder than a rabble-rouser, which suggests he is unlikely to vote for witnesses in the impeachment trial.
“Lamar is not looking for a one-time event to have what I call the shocking headline,” said Tom Griscom, a close friend of Mr. Alexander and former press secretary to Mr. Baker. “You’ve got a template of who he is over a career — that doesn’t change. He’s not looking to write a post-note at the back end of it.”
On policy matters, though, Mr. Alexander has not been afraid to part ways with Mr. Trump. While he has voted with the president 90 percent of the time, according to the website FiveThirtyEight, his departures are significant. He voted to overturn Mr. Trump’s plan to use military funds to build a border wall, fought the president over tariffs and sought to block him from withdrawing troops from Syria.
At 79, Mr. Alexander is an icon in Tennessee politics — twice elected governor; president of the University of Tennessee; education secretary to President George Bush; an unsuccessful presidential candidate in 1996 and 2000 and a senator for the past 17 years. Pale and bespectacled, he is regarded as a serious legislator (he oversees the Senate health committee) and an “institutionalist” — a guardian of the chamber and its traditions.
”I’ve always loved working with him; I’m a big fan of his,” said Senator Amy Klobuchar, Democrat of Minnesota, who is running for her party’s nomination for president. “I just think that he’s someone who really tries to get things done.”
John Geer, a political scientist at Vanderbilt University and co-director of the Vanderbilt Poll, said his surveys show a “strong majority” of Tennesseans believe Mr. Trump did “something wrong,” and while Mr. Alexander is under pressure from conservatives, “the Baker wing” of the Republican Party would stick with him if he voted for witnesses.
“He’s not voting for impeachment; he’s made that very clear,” Professor Geer said. “He’s voting to learn more, which is frankly something pretty easy to defend.”
Mr. Alexander got his start in politics working for Mr. Baker in the 1960s. In 1973, when Mr. Baker was the influential ranking minority member of the Senate Watergate Committee, he asked Mr. Alexander, a lawyer, to be his chief counsel. But Mr. Alexander turned down the job; he wanted to seek public office in Tennessee. He has modeled himself after Mr. Baker, adopting the late senator’s habit of giving careful thought to every decision.
Often forgotten about Mr. Baker is that his famous question was actually uttered in an effort to protect Nixon; only after months and months of hearings did he turn against the president. Victoria Bassetti, a former Senate aide and fellow at the Brennan Center for Justice, who has written about the episode, said Mr. Alexander’s situation is different.
“What happened with Howard Baker was the result of the slow, steady accumulation of wisdom and insight and just the scales dropping from his eyes over the course of months and months of close careful attention to what was going on,” she said. “And that’s not happening in the Senate today.”
What is happening instead is that many Republicans reflexively defend Mr. Trump, and those who are unwilling to increasingly feel crowded out of their party, vulnerable to primary challenges from the president’s loyal base. People close to Mr. Alexander deny that he is leaving the Senate for that reason. He simply wants to “go out at the top of his game,” as one friend put it.
But the politics of his state have shifted under Mr. Alexander’s feet. In 2014, he faced a tough primary challenge — his first serious competition in years — from a little-known state representative and conservative Tea Party candidate, Joe Carr. Although Mr. Alexander won the race handily, many in Tennessee say he would have almost certainly faced another primary fight this year.
For now, Mr. Alexander is eager to get back to accomplishing his highest legislative priority: a bipartisan package of bills aimed at lowering the cost of medical care, which has already passed his committee. But no matter what he does on impeachment, like Mr. Baker, he will almost certainly be remembered for it.
“The reality is that this is Lamar’s last year in the Senate,” said Bill Haslam, a former governor of Tennessee. “He would rather be working on legislation that he thinks can make a difference for the country. This is not how he would choose to spend the first month of his last year.”
Emily Cochrane contributed reporting.