(CNN) -- Kicking off a week-long push seen as outreach to independent and Democratic voters in crucial swing states, John McCain on Monday delivered a speech outlining his vision for combating global warming.
Sen. John McCain's stance on global warming has put him at odds with some members of his party.
"We stand warned by serious and credible scientists across the world that time is short and the dangers are great," McCain said in Portland, Oregon. "The most relevant question now is whether our own government is equal to the challenge."
McCain's commitment to fight global warming puts him at odds with some Republicans in Congress and with the Bush administration, which has not made climate change a top priority.
In his speech, the Arizona senator proposed capping carbon emissions incrementally, with the goal of returning to 1990 emission levels by the year 2020 using a cap-and-trade program.
Such a program would cap greenhouse gas emissions at certain levels, and allow more efficient energy producers to sell off emissions permits to other, less efficient companies, thereby creating market-wide incentives to reduce carbon output.
McCain believes this system will encourage companies to seek out more efficient means of production.
"As never before, the market would reward any person or company that seeks to invent, improve or acquire alternatives to carbon-based energy," he said.
McCain has also released a television ad in Oregon connecting climate change to increased destructive weather phenomena like hurricanes. The spot features a McCain voiceover saying, "It's not just a greenhouse gas issue, it's a national security issue." Watch the ad »
McCain will also speak about the environment on Tuesday in the neighboring state of Washington. Oregon and Washington are among several potential battleground states in the West, including California, Colorado, New Mexico and Nevada, where voters count the environment as a top issue.
However, McCain is not completely breaking with Republican orthodoxy on environmental matters. He agrees with the Bush administration's position on the Kyoto Protocol, which the United States has refused to ratify because large polluting nations like China and India are not obligated to reduce emissions.
McCain is also an ardent supporter of expanding nuclear power, a fact he mentions at nearly every campaign stop.
This week, the Democratic National Committee is accusing the presumptive Republican nominee of hypocrisy on the energy issue, emailing reporters a list of McCain advisers who have served as lobbyists for the oil industry.
Ahead of McCain's speech, DNC Chairman Howard Dean called McCain the "wrong choice" for voters who want "a true champion of the environment."
"Sen. McCain is once again trying to re-cast himself as a friend of the environment for the general election, but his record clearly shows that the only friends he really stands up for are his donors and the lobbyists running his campaign," Dean said in a statement. "No campaign rhetoric can change his record."
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