Campaigning on the taxpayers' dime

I've been following the President's travel schedule over the last few weeks, mostly out of curiosity. Maybe I shouldn't have been, but I was really surprised at how much campaigning is combined with official business. I'm assuming the official business is included so it's covered by the taxpayers, similar to a corporate employee scheduling a trip to San Francisco and spending half the day in meetings and half of it on Fisherman's Wharf.

Here are some examples of dates over the last week and a half that have included campaigning. The presumed campaign events are in bold/italics.

8/9

1:05 PM: The President arrives in Austin, Texas
2:05 PM: The President delivers remarks at a DNC finance event
3:00 PM: The President delivers remarks on higher education and our economy
4:30 PM: The President departs Austin, Texas en route Dallas, Texas
5:20 PM: The President arrives in Dallas, Texas
6:25 PM: The President attends a DSCC finance event
7:35 PM: The President departs Dallas, Texas en route Andrews Air Force Base

8/16

9:15 AM: The President departs the White House en route Andrews Air Force Base
9:30 AM: The President departs Andrews Air Force Base en route Milwaukee, Wisconsin
11:15 AM: The President arrives in Milwaukee, Wisconsin
11:50 AM: The President tours ZBB Corporation Manufacturing Facility
/12:10 PM: The President delivers remarks to workers
2:00 PM: Open for Questions: Gulf Seafood Safety with Dr. Jane Lubchenco
2:25 PM: The President delivers remarks at an event for Mayor Tom Barrett
3:25 PM: The President departs Milwaukee, Wisconsin en route Los Angeles, California
7:10 PM: The President arrives in Los Angeles, California
10:05 PM: The President delivers remarks at a DCCC finance event

8/17
12:00 PM: The President departs Los Angeles, California en route King County International Airport
12:00 PM: The Vice President has lunch with Elie Wiesel
1:00 PM: The Vice President meets with President of the AFL-CIO Richard Trumka
2:15 PM: The President arrives Seattle, Washington
2:15 PM: The Vice President meets with newly sworn-in U.S. Ambassador to Iraq James Jeffrey
2:40 PM: The President holds a round table discussion with small business owners
3:20 PM: The President delivers a statement to press
3:45 PM: The President delivers remarks at a finance event
5:35 PM: The President delivers remarks at a finance event
6:35 PM: The President departs Seattle, Washington en route Columbus, OH
10:20 PM: The President arrives in Columbus, OH

8/18

10:15 AM: The President meets with Columbus, Ohio family
10:50 AM: The President holds discussion on the economy
1:20 PM: The President delivers remarks at a reception for Governor Ted Strickland
2:25 PM: The President departs Columbus, Ohio en route Miami, Florida
4:45 PM: The President arrives in Miami, Florida
6:00 PM: The Vice President and Dr. Biden attend the funeral service for Senator Ted Stevens
6:10 PM: The President delivers remarks at a reception for the Florida Democratic Party
7:35: PM: The President departs Miami, Florida en route Andrews Air Force Base
9:45 PM: The President arrives at Andrews Air Force Base
10:00 PM: The President arrives at the White House

So 4 of the last 8 business days involved campaigning. 8 events, 6 cities, and 5 states.

I realize part of the President's job is selling his agenda. I have to wonder, though, how much the taxpayers spend to assist with his political campaign activity?

As a not-so-side-note, I imagine Governor Pawlenty's schedule isn't much different, though I wasn't able to track it down.