Seven months after deciding not to seek the presidency for a second time, Sen. John Kerry (D-Mass.) finally seems comfortable with his latest act on Capitol Hill.

The 2004 Democratic White House nominee has buried himself in legislative work by tackling health care, veterans, energy and environmental issues. He continuously drops bills and drafts amendments on an array of topics. And after once being thought of as a possible candidate for retirement, he is enthusiastic about seeking a fifth Senate term next year.

But Kerry is clearly watching closely as the 2008 presidential election unfolds. And a few I-told-you-so statements still escape from the mouth of the current “almost president” titleholder.

Kerry says he treads lightly with his four colleagues who are seeking the Democratic nomination next year.

“I really don’t have any” advice for Democratic Sens. Joseph Biden (Del.), Hillary Rodham Clinton (N.Y.), Chris Dodd (Conn.) and Barack Obama (Ill.), Kerry said in an interview last week.

If they seek his input, he happily complies, otherwise their conversations lead elsewhere, he said.

“If they ask questions, I answer questions,” Kerry said. “But I mean, it’s up to them to initiate; I don’t want to impose or insert myself inappropriately.”

Kerry does note that some of the candidates’ rhetoric — particularly on Iraq and health care reform — match his 2004 platform.

Kerry enjoys the freedom that comes with tearing off the presidential candidate shackles.

“I think people listen to what you’re saying and operate with a different light when you’re not a candidate,” he said. “You are not viewed through the prism of presidential politics.”

While it seems anyone running for president measures every word with near-flawless precision, Kerry said his statements always stem from genuine positions.

“I never felt constrained to speak out on something I believe in or to do what I think is right,” he said.

That led him to take the politically precarious stance he assumed last year when he forced the Senate to vote on an amendment that would have set a date for withdrawing U.S. troops from Iraq.

That amendment, which he offered with another Democratic Senator who declined the presidential spotlight this cycle, Wisconsin’s Russ Feingold, was not warmly received.

“I call the shots the way I see them, which is why I took the amendment down to the floor and got 13 votes last year, because I thought it was imperative and the right thing to do,” Kerry said.

“In fact, despite some of the unsettled feelings among some colleagues for taking that vote to the floor, by November already of that year [it had] become the closing argument of the Democratic Party, which is what I said would happen.”

Kerry savored his vindication last week when Senate Democrats unanimously voted for a proposal by Sens. Carl Levin (D-Mich.) and Jack Reed (D-R.I.) nearly identical to his.

“In essence, we got 13 votes and now we got over 50 — it’s become the Democratic Caucus position and I’m proud of that. I think that’s the leadership that I promised to try to offer and I think that I have.”

Just Friday afternoon, Clinton borrowed Kerry’s Iraq credentials in announcing that the pair will try to force the Bush administration to draw up a troop redeployment contingency plan.

That prompted a Pentagon official to launch verbal arrows at Clinton, which were promptly met by Kerry’s shield.

“This administration reminds us every day that they will say anything, do anything, and twist any truth to avoid accountability,” Kerry fired back in a news release.

“Their latest assault on Sen. Clinton comes from a tired partisan playbook and it’s a disgrace,” he continued. “They ought to be planning to save lives — not plotting to save face.”

Some Republicans met Kerry’s January announcement that he would only run for re-election next year with boasts that he would fail there too.

So far, Kerry has more than $6 million in the bank and no serious GOP challenger, and Massachusetts has no Republicans in its 12-member Congressional delegation.

If Republicans attempt to turn him into this cycle’s Tom Daschle — the GOP aggressively sought, and achieved, the defeat of the former Senate Democratic Leader from South Dakota in 2004 — Kerry has no fears.

“I’ve run against strong and tough candidates previously,” Kerry said. “I’ve run against the sitting president of the United States. I know how to go out and campaign and raise money; I also know that you take nothing for granted.”

The biggest difference between running for president and running for anything else is scope, Kerry said.

“It’s a lot easier. You get home and sleep in your own bed at night,” he said. “You get from one end of the state to the other in the same day. I’m enjoying it.”

That does not mean Kerry intends to exit the national stage entirely, however.

He still wields JohnKerry.com, his powerful, 3 million-names-strong e-mail list, which he amassed during the 2004 campaign.

“We were able to do more than any other potential 2008 candidate [in the past cycle]” to help Democrats up and down the ballot, Kerry said. “We raised more money and gave more money than anyone else.”

He raised $14 million for 260 candidates and campaigned in 35 states.

“We’re going to continue to do that, mindful, obviously, that my first priority is Massachusetts,” Kerry said.