The mayors of Minneapolis and St. Paul will hold a news conference and pep rally Monday morning, hoping to inspire more people to volunteer for the Republican National Convention. Behind the scenes, organizers have said they're having a tough time recruiting volunteers, especially among the young. So far, fewer than half the 10,000 volunteers originally hoped for have signed up.

There's quite a different story being told in Denver. More than 26,000 people have signed up to volunteer to work around the Democratic National Convention; a third of those from outside Colorado.

The difference is the Obama factor. Barack Obama's campaign has drawn huge numbers of young people into politics. John McCain? Not so much, if the volunteer situation in Minnesota is any indication.

The mayors will stress that volunteering isn't so much about partisan politics as a chance to "be a part of history.'' A "rewards package'' also is being created for those who volunteer.