MEDFORD — Former President Bill Clinton warmed up Oregon for a future visit from his wife, starting a two-day sweep through the state whose May primary has taken on new significance with the tightness of the race for the Democratic presidential nomination.

“I think she’s the best change-maker I ever knew,” Clinton told the crowd of about 2,500 people at North Medford High School.

He was to make further appearances today in Portland, Salem and Bend.

Clinton noted his wife’s work as a U.S. senator to get benefits for New York police and firefighters who breathed polluted air after the 9/11 attack and how she reached across the aisle to work on curbing global warming with Sen. John McCain, the presumptive Republican presidential nominee.

In a reference to the loss of federal timber payments to Oregon counties since logging was cut back to protect the northern spotted owl and salmon, Clinton said it was wrong for the government to make changes in resource management without giving people compensation.

Clinton said every county in Oregon would benefit from his wife’s support for small biomass energy plants that burn agriculture and logging wastes. He added that the government would do better to support development of new sources of energy, which have a high potential for job growth, rather than subsidizing oil companies.

He said Mrs. Clinton had a strong commitment to veterans, dating to her eight years as first lady, when she asked to be “the point person” on helping victims of Agent Orange, an herbicide sprayed in Vietnam, and would work to improve care for personnel returning from Iraq.

Running an hour late after speaking to the Democratic state convention in San Jose, Calif., Clinton spoke for more than an hour, but took no questions from press or voters.

Clinton’s visit came one week after Sen. Barack Obama also spent two days in Oregon.

At stake during the state’s May 20 primary are 52 pledged delegates that will be divided in proportion to the primary vote, 12 superdelegates and another delegate to be chosen at the state convention.

With 10 primaries to go, Sen. Clinton has only a slim chance of overcoming Obama’s lead in pledged delegates, even with an upset win in Oregon. Her stepped- up criticisms of Obama have led to worries she could hurt his chances to defeat Republican Sen. John McCain in the fall if she does not win the nomination herself.

Hillary Clinton’s campaign schedule indicates she will likely be in the state during the week of April 6.