John McCain is traveling across Florida by bus today, stressing his commitment to low taxes.

The campaign bills this as the "Joe the Plumber" tour, in honor of the Ohio man who challenged Barack Obama's plan to raise taxes on families and small businesses making more than a quarter-million dollars a year.

Bus tours are a colorful staple of the campaign trail, a chance for the candidate to hit numerous small towns in a single day — in this case along Florida's vote-rich I-4 corridor.

For traveling reporters, though, bus tours are challenging: long stretches on the road with no power for their laptop computers, and today at least a particularly fragrant back-of-the-bus bathroom.

"We actually need Joe the Plumber," one reporter joked.