* Both plan rallies in the same town
* Polls show close race but slight advantage to Obama
* Trying to win voters from the other side
By Patricia Zengerle and Matt Spetalnick
DUBUQUE, Iowa/MENTOR, Ohio, Nov 3 (Reuters) - After months spent rallying their most reliable supporters, Republican Mitt Romney and President Barack Obama reached out on Saturday to the small sliver of voters who remain undecided in the final days before Tuesday's presidential election.
With the race in a dead heat nationally, both candidates hopscotched across the country in a bid to secure any possible advantage ahead of Election Day. That meant another round of campaigning in the handful of states that remain competitive and a last-minute effort to pull votes from the other side.
At airport rallies in New Hampshire and Iowa, Romney urged supporters to try to sway friends and neighbors who back Obama. He said he would reach out to Democrats as well if elected - a stance that could appeal to independent voters who have little stomach for partisan gridlock.
"I want you to reach across the street to the neighbor, who has that other sign in his front yard. And I'm going to reach across the aisle in Washington, D.C., to the politicians who are working for the other candidate," Romney told about 2,000 people at an airport rally in Dubuque, Iowa.
In Ohio, Obama hammered Romney for opposing his bailout of the auto industry and trying to scare workers by saying inaccurately that Chrysler planned to shift jobs to China.
"I understand that Governor Romney's having a hard time here in Ohio because he was against saving the auto industry," Obama said.
About one in eight jobs in Ohio is tied to auto manufacturing. The bailout appears to have boosted Obama's prospects in the Rust Belt state, especially among the working-class white men who are heavily backing Romney in much of the rest of the country.
"I've been a Republican for 35 years and I've never voted for a Democrat on the federal level - until now," retiree Patrick Dorsey said as he waited for Obama to speak. "Economically, Romney's just going to make the rich richer."
TIGHT RACE IN POLLS
Romney will have a hard time winning the White House if he does not carry Ohio, and a Reuters/Ipsos poll released on Saturday showed him trailing Obama by a statistically meaningless margin of 1 percentage point in the state. Other polls show him trailing by a larger margin in Ohio.
The race for the White House remains effectively tied at a national level with 47 percent backing Obama and 46 percent backing Romney, according to a Reuters/Ipsos daily tracking poll released on Saturday.
The narrow scope of the race has been evident for months but it was shown vividly on Saturday, when Obama was due to campaign in Dubuque six hours after Romney's visit.
Still, analysts say Obama holds an edge in many of the eight or nine competitive states that will determine who controls the White House. Reuters/Ipsos polls released on Saturday showed Obama leading by 3 percentage points in Virginia but trailing by 2 points in Colorado. The two were dead even in Florida. All the results were within the credibility interval, a measurement of the accuracy of online polls.
Other surveys generally show Obama leading by narrow margins in Wisconsin, Nevada, New Hampshire and Iowa. Romney is considered to have the edge in North Carolina.
Romney has tried to expand the battlefield over the past week to states that had been considered beyond his reach.
"We win Pennsylvania, we save America in three days," Romney's vice presidential running mate, Paul Ryan, said at an airport rally in the state capital, Harrisburg.
Ryan is due to visit Minnesota on Sunday, another state that has been considered solidly Democratic. Romney himself is due to speak in Pennsylvania on Sunday.
Obama officials say the Romney campaign is visiting those states out of desperation because he has been unable to establish a clear lead in other battleground states.
Nevertheless, the Obama campaign is dispatching Vice President Joe Biden's wife, Jill Biden, to Pennsylvania and former President Bill Clinton to Minnesota.
Obama started the day at the federal government's disaster-relief headquarters in Washington, where he received an update on the efforts to help Northeastern coastal states recover from devastating storm Sandy.
The storm has afforded the Democrat an opportunity to rise above the fray of campaigning. But it has also raised the stakes for him to show his administration can respond quickly and effectively in a crisis, as residents of New York and New Jersey vent frustration at power outages and gasoline shortages.
"He's focused on it every moment he's not speaking on the stage," Obama campaign spokeswoman Jen Psaki told reporters aboard Air Force One.