U.S. Sen. Jon Tester, left, listens as U.S. Sen. Jim Webb of Virginia joins him Tuesday Oct. 2, 2012 for a day of campaigning in Helena, Mont. (Matt Gouras/AP)

At a restaurant in north-central Montana, Sen. James Webb looked out at about 150 supporters of his best friend on Capitol Hill and acknowledged how rare it was to be out on the road, particularly in faraway Great Falls.

“You don’t come up to this part of the United States on your way to anywhere else,” Webb joked Monday night, drawing laughter from the crowd.

He focused his remarks on his bond with Sen. Jon Tester, which was forged shortly after the two Democrats narrowly won their 2006 Senate races. “I told Jon that I would do anything I could to make sure he remains in the United States Senate,” Webb said.

Tester may hope to return to Congress in January, but Webb won’t. The Virginian is retiring after one term in the Senate, in part because of his distaste for the rigors of campaigning.

Now, as some fellow Democrats seek his help on the trail — including the man hoping to succeed him, former governor Timothy M. Kaine — Webb is picking his spots, mostly helping candidates to whom he feels personally close. In the market for campaign surrogates, Webb’s relative scarcity makes him a valuable commodity.

He generated buzz last week after his passionate speech introducing President Obama at a rally in Virginia Beach.

Webb, a decorated Marine veteran and former Navy secretary, subtly criticized Mitt Romney for not being drafted into the military during the Vietnam War and not-so-subtly attacked the Republican presidential nominee for his “47 percent” remarks and for failing to mention veterans and the Afghanistan war during his convention speech.

Veterans, Webb said, “are owed, if nothing else, at least a mention, some word of thanks and respect, when a presidential candidate who is their generational peer makes a speech accepting his party’s nomination to be commander in chief.”

Although he has made it clear that he supports Obama, Webb has also been outspoken about the issues on which he disagrees with his party and its standard-bearer. And Webb has said very little about Romney, so his remarks last week struck a chord.

Garren Shipley, a spokesman for the Virginia Republican Party, said that Webb’s public appearances only served to highlight the gulf between him and fellow Democrats.

“Jim Webb has been effective because he represents the opposite of what Obama and Kaine stand for,” Shipley said. “If anything, he’s effective camouflage. Both Obama and Kaine can point to Webb to try to hide the fact that they’re lockstep, big-government, high-tax liberals.”

Asked in Montana how he could campaign for Obama after criticizing him on some issues, Webb said: “Family arguments are one thing, but in terms of where the country needs to go, it’s quite another.”

Although he is not a daily presence on the trail, Webb has done his share of politicking in recent months.

“I’ve been out,” he said. “I’ve been with Bob Kerrey, I’ve been with Claire McCaskill.”

Kerrey, who is running for an open Senate seat in Nebraska, is a friend of Webb’s from their shared experience serving in the Vietnam War; McCaskill, running for reelection to the Senate in Missouri, also won her first race in 2006 and has been very close friends with Webb and Tester ever since.

In Virginia, Webb was a featured speaker at June’s state Democratic convention, where there was a reception in his honor (although he skipped the Democratic National Convention in Charlotte last month). Last week, he attended a dinner in Scott County for Anthony Flaccavento (D), who is fighting an uphill battle to unseat Rep. Morgan Griffith (R).

Webb is slated to do a “dessert reception and fundraiser” in Old Town Alexandria for the state party on Wednesday night and a Saturday evening event in Oakton for the 10th District Democratic Committee.

Most notably, he has made some appearances with Kaine, who is running against the man Webb beat in 2006 — George Allen (R). Webb joined Kaine for a veterans roundtable in Tysons Corner in April and did fundraising receptions for him in August and September. The two Democrats are expected to appear at another event in the Hampton Roads area this month.

In Great Falls, Webb thanked the veterans in the crowd for their service, relating stories about growing up an Air Force brat. He did not criticize Tester’s opponent, Rep. Dennis Rehberg (R-Mont.), instead focusing on Tester being a true Montanan.

Afterward, Webb told reporters that he had “no comment” about Rehberg, signaling that despite his barbs aimed at Romney the previous week, his stumping would not necessarily involve the normal surrogate work of tearing apart the opponent.

On Tuesday morning, Webb attended a veterans event in Great Falls with Tester, then drove to Helena, where he headlined a rally outside the state Capitol. Afterward, a couple dozen Montanans came up to meet Webb, who is nowhere near the back-slapping pol that Tester is. As each person greeted Webb, he gave a simple response: “I appreciate you being here.”

He was on an afternoon flight out of Helena, his campaign swing complete.

Kane reported from Montana.