Reince Priebus, the GOP chairman, pointed to recent gains for Romney that have lifted him to a virtual tie in most national polls. "The challenger always wins in a tie race," he said.
With time running out, both campaigns appeared to be fine-tuning their map of the states where they're campaigning the hardest.
A senior Republican official, speaking on the condition of anonymity to disclose private deliberations, said Sunday that the Romney team was seriously discussing sending Romney, Ryan or both to Minnesota during the final week. The state hasn't gone Republican in the presidential race since 1972, but recent polling shows a tighter race there than most anticipated.
In a flashback to the 2008 race, Obama's campaign announced that Biden will campaign Thursday in Pennsylvania, reprising a visit to his hometown of Scranton that he made during the final week four years ago. Pennsylvania, too, has been Democratic territory in recent years, but Romney has continued to contest the state with an advertising assist from the Republican Party.
Axelrod, Priebus and McDonnell spoke on CNN's "State of the Union." Warner spoke on "Fox News Sunday."
Lederman reported from Washington. Associated Press writers Philip Elliott in Ohio, Brian Bakst in Minnesota and Jim Kuhnhenn and Julie Pace in Washington contributed to this report.
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