Washington ? The first caucuses of the 2008 presidential campaign are more than two years in the distance, but Iowa’s interest in ethanol knows no season.

That may help explain why Sen. John Kerry, D-Mass., nearly alone among senators from the Northeast, voted recently to fend off an attack on government support for the corn-based fuel alternative.

And why Sen. George Allen cast a similar vote, marking a turnabout in his position. It left him on the opposite side from Virginia’s other Republican senator, John Warner.

“It doesn’t require presidential ambitions for United States senators to want an energy policy that benefits consumers and relies on American farmers, not the Saudi royal family,” said David Wade, a spokesman for Kerry, the Democratic presidential candidate last year and a potential contender in 2008.

Energy legislation customarily underscores regional rather than party differences in the Senate. But presidential ambition also poked through during last week’s debate.

Corn is abundant in Iowa, where it is processed into a fuel additive in increasingly large amounts. Iowa also stages party caucuses every four years that provide the first major campaign test of the presidential campaign.

Of the 18 senators from six New England states plus New York, Pennsylvania and New Jersey, only Kerry and Sen. Judd Gregg, R-N.H., sided with ethanol on the important vote.

Fifteen senators voted the other way, including Massachusetts’ Edward M. Kennedy. Sen. James Jeffords, the Vermont independent, did not vote.

Among other potential presidential contenders, Senate Majority Leader Bill Frist, R-Tenn., voted to protect the expanded mandate, as did Sens. Sam Brownback, R-Kan., Chuck Hagel, R-Neb., and Evan Bayh, D-Ind. All are from states where corn is grown.

Sens. John McCain, R-Ariz., Hillary Rodham Clinton, D-N.Y., and Rick Santorum, R-Pa., also voted against the wishes of ethanol supporters.

Sen. Charles Schumer, D-N.Y., led the effort to keep the ethanol-related provisions out of the bill, citing the cost of shipping the additive, which cannot move through existing pipelines.

Illinois is No. 2 behind Iowa in ethanol production. Kansas is No. 7.