Like a lot of employees, Verizon lobbyist Robert Fisher has a cache of vacation days he’s going to tap before the end of the year. But unlike most people, Fisher isn’t planning on much rest and relaxation — and he’s definitely not going anywhere tropical.

Just before Christmas, Fisher has booked a trip to New Hampshire to volunteer for the presidential campaign of his one-time boss, Sen. John McCain (R-Ariz.).

“He’s taught me so much about politics and life, I’ll do anything for the guy,” said Fisher, who has already used personal time off to traipse to Iowa on McCain’s behalf. “I mostly do just advance work. It’s not glamorous, but it’s work that needs to be done.”

Fisher is one of many lobbyists around town who are answering the call of jittery presidential campaigns that want bodies during this holiday season.

Lobbyists will knock on voters’ doors or dial up their phone lines, lick envelopes, watch the polls, help organize events and offer last-minute strategic advice as the campaigns hit the final stretch to the Iowa caucuses on Jan. 3 and the New Hampshire primary slated for Jan. 8.

“Nobody likes to get on the phones and dial voters, but that’s direct voter contact and those are just the things that you have to do,” added Fisher, 34, who is a federal government relations vice president at Verizon and spent six years working for McCain, the one-time chairman of the Senate Commerce Committee. “It’s fun. It’s exhilarating.”

Dutko Worldwide lobbyist Ron Kaufman, one of the earliest inside-the-Beltway supporters of former Massachusetts Gov. Mitt Romney (R), said he is planning to spend Christmas in Iowa and then proceed to New Hampshire. His oldest daughter, he added, will be in Costa Rica for the holiday season, and he’s not sure about other family members.

“You’re going to see a whole bunch of people pulling up stakes and heading out of town,” said Kaufman, an unpaid senior adviser to Romney’s campaign. “The polls are going to tighten. … I would love to knock on doors, hold signs at intersections, go to coffee shops early in the morning and spread the word.”

Kaufman and Fisher will run into plenty of their Democratic colleagues from K Street.

In Iowa, Barbara Leach, a consultant and president of the progressive group My Rural America, is heading to Iowa on Jan. 1. Leach, an Iowan who served in the Agriculture and Transportation departments of former President Bill Clinton, plans to participate in the caucus in Johnston, Iowa, northwest of Des Moines.

A former vice chairwoman of the Iowa Democratic party from 1980 to 1987, Leach is supporting Sen. Hillary Rodham Clinton (D-N.Y.). (Although she runs her business from D.C., Leach is still an Iowa resident.)

Leach stressed that her group is neutral, so her support for Clinton is personal and she’s using vacation time.

When she gets there, she said, “you see who’s been identified and then move forward to talk with your circles of influence. I’m from western Iowa originally, so it might be that I would call some of my friends in western Iowa.”

Leach also keeps a personal e-mail list of Democratic and progressive voters, and she said she has received requests to send out calls for help from most of the candidates. “I think the Democrats have the strongest team of candidates that I really have ever seen,” said Leach, who first participated in the Iowa caucus in 1968 when she supported Bobby Kennedy.

Even though Sen. Barack Obama (D-Ill.) won’t take a dime from registered federal lobbyists for his presidential coffers, his campaign has solicited their help and some have answered. Andy Rosenberg, a lobbyist with Ogilvy Government Relations and an early supporter of the Draft Obama movement, said no one from the campaign asked him to go, but he is taking a weekend starting Jan. 4 to do field work and other volunteer activities for Obama’s operation in the Granite State.

“I’m staying with people I got to know through the Draft Obama movement, who are now part of the official campaign,” he said. “I was up in Manchester for his speech before he announced [his candidacy], and it was a really festive atmosphere. He was incredibly well-received. This is a fun way to finish this, to complete the cycle.”

It’s not always clear why lobbyists volunteer for the campaigns, especially when they give up personal time during the holiday season.

Most say they get involved in everything from grunt work to fundraising at the presidential level simply because they want to help their candidate of choice. But it also can be especially good for business because it helps lobbyists burnish new contacts and reconnect with old ones out on the campaign trail.

Lobbyists, like all campaign volunteers, must abide by campaign finance laws. Larry Noble, a counsel at Skadden, Arps, Slate, Meagher & Flom and a former general counsel at the Federal Election Commission, said lobbyists need to take vacation or leave time and cannot receive special treatment from their companies.

“They have to follow the same rules everybody else follows,” Noble said. If lobbyists pick up the tab for posters at a printing business, they must either be reimbursed by the campaign or the campaign must report the cost as an in-kind donation subject to the contribution limits.

Not everyone finds the idea of spending the holiday season in the field appealing.

GOP lobbyist Dan Mattoon, who supports McCain, said you won’t find him out there. “There’s people still hung over on Jan. 3,” Mattoon said, referring to the Iowa caucus date.

And Heather Podesta, a lobbyist who runs her own shop, Heather Podesta + Partners, said her strength is working the phones from closer to home. “I have been to Iowa this year,” said Podesta, who supports Clinton. “My plan is to spend the holidays on the phone, dialing for dollars for Hillary.”