As Iraq War Commander General David Petraeus goes before two U.S. Senate committees today, it will be difficult not to think about this day in political terms, as all three Senators running for President return for a day focused on Iraq.

The first hearing today is before the Senate Armed Services Committee, which counts both Sen. John McCain and Sen. Hillary Clinton as members.

McCain is the top Republican on the committee, so he will get a lot of early face time at this hearing.  He will be able to give an opening statement along with the Democratic Chairman Sen. Carl Levin of Michigan and then will get to ask the second round of questions.

In other words, McCain will be on the news for much of the morning and into the afternoon, while Clinton and Obama wait.

Sen. Clinton is well down the list on the Armed Services panel in terms of seniority, so it will take awhile to get to her, especially with 10 minutes of questions per Senator.

But Clinton is in better shape in terms of PR than Sen. Barack Obama, who will be part of an afternoon hearing before the Senate Foreign Relations Committee.

That doesn't begin until 2:30 pm, and after opening statements by the General and the U.S. Ambassador to Iraq and at least two Senators, it's likely that Obama's Q&A won't occur that long before the Evening News shows begin.

In other words, the news advantage goes to McCain overall, with Clinton second.  Her questions to General Petraeus will get a lot more attention that Obama, unless Obama creates some kind of verbal dustup.

Last week the chairs of the two committees involved today both said that no special accommodations would be made for any of the Presidential contenders.

That means that Clinton and Obama will have to show up early at the hearings to claim their spots in line for questions and then basically cool their jets there most of the day.

A little bit different than what they've been dealing with the past few months, eh?

Outside of Senators McCain, Clinton and Obama though, there are a host of familiar characters who will drive news coverage as well.

For the Democrats, you've got Sen. Edward Kennedy and Sen. Robert Byrd, both of whom are staunch opponents of Bush Administration policies.

But then Sen. Joe Lieberman, the Democrat turned Independent who backs the war, will get his chance to say a few things as well.

In the afternoon hearing, you've got several former candidates for the White House in Sen. Joe Biden and Sen. Chris Dodd, plus the Democratic nominee from four years ago, Sen. John Kerry.

Note to McCain, Clinton & Obama:  When you get your chance with General Petraeus, don't blow it.