DENVER | Sen. John McCain's efforts to tap voter discontent over soaring energy prices have helped produce his first poll lead in Colorado, a near dead-heat in Michigan and improving numbers in two other states.
The Quinnipiac University poll released Thursday showed Mr. McCain topping Democratic presidential opponent Sen.Barack Obama 46 percent to 44 percent in Colorado, after trailing by five percentage points a month ago. The results surprised politicos in the state, many of whom were predicting that Mr. Obama would win Colorado as part of the Democratic Party's recent successes here.
"We'd gotten into this mind-set that 2008 would be a good year for the Democrats," said Denver pollster Floyd Ciruli. "What this shows is that issues still matter."
The fortunes are changing as Mr. McCain and Republicans on Capitol Hill make a concerted effort to overcome Democratic hurdles to expand U.S. areas open to drilling and as Democratic presidential candidate Barack Obama focuses on foreign relations in a trip overseas.
"The results show increased support for additional drilling, which McCain supports and Obama opposes," said Peter Brown, assistant director of the Quinnipiac University Polling Institute in Hamden, Conn., which conducted the survey with the Wall Street Journal and Washingtonpost.com.
"Roughly one in 10 voters say they have changed their minds and now favor drilling because of the jump in energy prices," he said. "They support Obama, but with voters saying that the energy issue is now more important to their presidential vote than is the war in Iraq, this group represents an opportunity for the Republican."
In Colorado, Republicans have had to hand Democrats control of both legislative houses, the governor's office and a U.S. Senate seat since 2004. Still, Republicans consider it essential for Mr. McCain to win a state that supported President Bush in 2004.
Campaign ads here tout Mr. McCain's support for a portfolio of energy strategies, including wind and solar power, as well as expanded drilling offshore. The Republican candidate continues to oppose drilling in the Arctic National Wildlife Refuge in Alaska.
"John McCain has presented a plan for more domestic oil drilling, a gas tax suspension, more nuclear power, and Barack Obama has been stubbornly opposed. Voters know that if you're not part of the solution, you're part of the problem," campaign spokesman Tucker Bounds said.
Mr. Obama has called for energy alternatives, conservation and restrictions on speculation.
"The energy issue was working for the Democrats until April, when gas prices hit $4 [per gallon], and then people began looking at traditional sources like oil, which Republicans dominate," said Mr. Ciruli. "When you're paying $4 and looking at $5, you start to get very realistic about your energy sources."
The energy issue also is creating a divide in Washington.
House Republicans on Thursday blocked a Democratic proposal to sell 10 percent of the nation's emergency petroleum reserve, or about 70 million barrels, on the open market in the next six months. Proceeds from the sales would have been used to buy heavy crude, which is cheaper, to replace the reserve.
It was the third time in recent weeks that Democratic leaders have refused to allow amendments on energy-related measures, a move they say is necessary to expedite bills of national importance. Republicans accuse Democrats of employing the tactic solely to avoid a vote on a Republican proposal to lift a ban on offshore drilling.
The Quinnipiac Poll focused on four states considered critical to winning the White House in November.
Mr. Obama continued to lead in Michigan, Minnesota and Wisconsin, but his margin of victory slipped in all three states. In Minnesota, Mr. Obama's edge over Mr. McCain dropped from 54 percent to 37 percent last month to 46 percent to 44 percent in the latest poll.
In Michigan, Mr. Obama topped Mr. McCain by 46 percent to 42 percent, compared with 48 percent to 42 percent last month. In Wisconsin, Mr. Obama stumbled slightly, leading 50 percent to 39 percent compared with 52 percent to 39 percent last month.
"Senator Barack Obama's post-primary bubble hasn't burst, but it is leaking a bit," Mr. Brown said.
A Pew Hispanic Center poll showed Mr. Obama winning 66 percent to Mr. McCain's 23 percent among Hispanics registered to vote.
Mr. Bush won 40 percent of the Hispanic vote in 2004, and Mr. McCain has made Hispanic outreach a hallmark of his congressional career and of his presidential campaign. The poll found that Mr. McCain is paying the cost of the Republican Party's loss of Hispanic voters overall.
The poll also found Mr. Obama's race is a net positive among Hispanic voters.
A Fox News/Opinion Dynamics poll found Mr. Obama leading Mr. McCain 40 percent to 37 percent nationwide, but that the Democrat's lead increased to 48 percent to 39 percent if Mr. Obama selects Sen. Hillary Rodham Clinton of New York as his running mate and Mr. McCain chooses former Massachusetts Gov. Mitt Romney as his.
That suggests a significant number of Mrs. Clinton's supporters are awaiting Mr. Obama's decision on a vice-presidential nominee.
cSean Lengell, reporting in Washington, contributed to this article.