Nov. 2 (Bloomberg) -- Barack Obama and John McCain chased each other and the presidency across a brace of battleground states as the race for the White House entered its final 48 hours.

Democratic nominee Obama spent his day in Ohio, one of several typically Republican-leaning states that he has put in play. Republican candidate McCain was in Pennsylvania, hoping to wrest that state away from the Democrats with a late surge.

Obama, 47, once again sought to tie McCain to President George W. Bush, calling him a ``sidekick'' of the Republican incumbent.

``The last thing we can afford is four more years of the same old tired, stale, old economic theories,'' Obama said at a rally of 60,000 supporters in front of the state Capitol in Columbus. The Illinois senator planned an appearance later in the day in Cleveland with rock singer Bruce Springsteen and a nighttime rally in Cincinnati.

McCain, 72, said he would ``hold the line on taxes'' and cut government spending. And he urged supporters to ignore polls showing him trailing his opponent.

``Nothing is inevitable here,'' the Arizona senator said at a rally of about 2,000 people at the University of Scranton, his second event of the day in the state. ``We never give up. We never quit.''

Pennsylvania Challenge

McCain's emphasis on Pennsylvania -- which has voted Democratic in every presidential contest since 1988 -- reflected two realities. The first is that Obama is contesting a host of states won by Bush in 2000 and 2004, making it essential that McCain challenge Obama on Democratic turf.

The second is that several recent polls have shown a dwindling Obama lead in Pennsylvania. For example, a Muhlenberg College survey taken Oct. 28 through Nov. 1 showed Obama ahead by 7 percentage points; an Oct. 23-27 survey by the same pollster had Obama ahead by 12 percentage points.

``The most important state to watch right now is Pennsylvania,'' said McCain's campaign manager, Rick Davis, on the ``Fox News Sunday'' program.

While the two presidential candidates mostly repeated familiar arguments on the stump, McCain's running mate, Alaska Governor Sarah Palin, tried to open a new front.

Coal Industry

Palin, campaigning in southern Ohio, seized on a January recording of Obama telling the San Francisco Chronicle newspaper that his cap-and-trade energy proposal would ``bankrupt'' those building coal-fired power plants.

``You should have known about this so you have better decision-making information in the voting booth,'' she said in Marietta, Ohio.

``He's comfortable letting that happen,'' said Palin, pledging that she and McCain are committed to the coal industries in Ohio and neighboring West Virginia and Pennsylvania.

Obama favors curbing emissions that contribute to global climate change through a system of charging fees to those who emit such gases.

``So if somebody wants to build a coal-powered plant, they can; it's just that it will bankrupt them because they're going to be charged a huge sum for all that greenhouse gas that's being emitted,'' Obama told the newspaper, according to a video of the interview posted on the Web site youtube.com.

In response, Ohio Governor Ted Strickland, an Obama supporter, called Palin's charge a ``last-minute, desperate distortion'' of Obama's record.

Coal-State Senator

``After John McCain said he'd like to `transition away from coal entirely,' his campaign is hardly in a position to criticize a coal-state senator like Barack Obama who has outlined a $150 billion investment in clean coal and other technologies to create jobs and build a new energy economy,'' Strickland said in a statement.

Much of the day's discussion, both on the campaign trail and television talk shows, centered on polls showing Obama poised for victory on Nov. 4. The Web site Real Clear Politics showed Obama leading by 6.4 percentage points nationally, according to an average of recent polls, and ahead in states with a total of 278 electoral votes, 8 more than needed for victory.

McCain and his aides and surrogates said the race was tightening and predicted a comeback victory.

``I know the momentum is there,'' McCain told 2,000 supporters in a high school gym in Wallingford, Pennsylvania. ``We're going to win this election. I know it.''

Davis said the election was ``moving very quickly'' in McCain's direction. ``We're in for a slam-bang finish,'' Davis said. ``John McCain may be the greatest closer politician of all time.''

Bush States

Obama aides David Axelrod and David Plouffe dismissed that argument and said McCain was being forced to defend a host of states Bush won in 2004 -- including Virgina, Colorado, Nevada and North Carolina -- that are now up for grabs.

Axelrod said on ABC's ``This Week'' show that prevailing in those states would be important both for winning the election and fulfilling Obama's goal to ``get past this red state-blue state kind of paradigm that we've been locked into.''

They also pointed to indications that early voting in states such as Ohio, North Carolina and Florida favored their candidate.

At the Columbus rally, Obama asked for a show of hands of those who had voted early, and most of the crowed indicated they had.

At the same time, Axelrod warned Obama supporters against any complacency. ``You've still got to vote, and that's our main message,'' he said.

Advertising Blitz

Both campaigns are spending for a blitz of advertising and get-out-the-vote efforts, with Obama putting ads on the air in Georgia and North Dakota as well in McCain's home state of Arizona. McCain's advisers said the candidate and the Republican Party would together outspend Obama on television over the last week of the campaign by about $10 million.

Tomorrow, the last full day of campaigning, Palin will appear in Ohio, Missouri, Iowa, Colorado, Nevada and Alaska. McCain will campaign in Florida, Virginia, Pennsylvania, Indiana, New Mexico, Nevada and finish up in Prescott, Arizona, at the Yavapai County Courthouse, where he has opened and closed most of his political campaigns.

Obama will stump in Florida, North Carolina and Virginia, while Biden will campaign in Missouri, Ohio and Pennsylvania.

To contact the reporters responsible for this story: Ken Fireman in Washington at kfireman1@bloomberg.netEdwin Chen in Scranton, Pennsylvania at echen32@bloomberg.net; Julianna Goldman in Columbus, Ohio, at jgoldman6@bloomberg.net

Last Updated: November 2, 2008 17:31 EST