Republican presidential hopeful John McCain hasn’t voted in the Senate since April 8.

That’s when McCain and presumptive Democratic nominee Barack Obama joined 90 other senators in voting to limit debate on a proposal aimed at stemming the tide of home foreclosures. Two and a half months later, the Senate voted again Tuesday to limit debate on housing legislation, a new version this time (HR 3221). Neither McCain, R-Ariz., nor Obama, D-Ill., showed up for the 83-9 vote.

McCain was campaigning in California, where he called on the federal government to embrace green technologies for vehicles and buildings. Obama talked about his energy policy during a campaign stop in Las Vegas.

Former presidential contender Hillary Rodham Clinton , D-N.Y., missed the housing vote but did appear a little later for a party luncheon.

“If there’s an important vote, or there’s a moment where they can actually advance part of the agenda, then they should be here,” said John Kerry , D-Mass., his party’s White House nominee four years ago. “But otherwise, I think the job of running for president is really too important and too big to be tied down here.”

Obama, who voted every week or two during the lengthy primary campaign, has not voted in three weeks. He has been in Washington several times during that period to meet with various groups, some on Capitol Hill.

Obama may return to the Senate later this week to vote on a spending bill (HR 2642) that includes money for military operations in Iraq and Afghanistan as well as expanded educational benefits for service members and extended unemployment insurance.

But there’s a risk anytime a presidential candidate casts a vote, since bills can be minefields of potential attack ads.

“Votes are very complicated, and when a member comes back to vote it puts his or her vote on record,” said Assistant Senate Historian Betty K. Koed, “There’s lots of confusion about just what a simple yes or no vote can mean.”

That’s part of the reason the McCain and Obama camps are relying on statements of support or opposition to legislation pending in the Senate, rather than votes, to establish their candidate’s position. Statements allow the candidate to express his position on his own terms, staying on message.

Both candidates, for example, issued statements announcing their support for limiting debate on a bill designed to combat climate change. But neither appeared to vote on the measure (S 3036).

Obama’s campaign issued a statement on June 20 declaring that the Democrat supported a compromise proposal to rewrite a warrantless surveillance law, but Obama is not expected to vote on the legislation (HR 6304) this week. Civil libertarians oppose the measure.

Only When He’s Needed