As the 2008 presidential race shapes up and heats up, voters may get the impression that it is a battle between two well-financed pressure groups. They are already being bombarded with television and newspaper ads, plus segments on YouTube, telling them what to think and how to vote on the main political issue: the war in Iraq.

MoveOn.org, already a well-known voice against the war for liberal activists, began in the Clinton impeachment debate as an online petition urging Congress to merely censure him and move on to other business. It now has become a political powerhouse. After the Sept. 11, 2001, attacks it merged with the MoveOn Peace campaign founded by Eli Pariser, a Maine native to become MoveOn.org Political Action. The overall organization claims 3.3 million members and raised $25 million in the past 18 months.

In many minds, MoveOn stumbled when it called Gen. David Petraeus “General Betray us.” Congress, including many Democrats, denounced this, but MoveOn refused to apologize and reaped thousands of new members.

Enter Freedom’s Watch, a group of conservatives and Republicans with close ties to the White House, which opened a $15 million advertising campaign defending President Bush’s Iraq war strategy. Among its first moves were denunciations of Iranian President Ahmadinejad’s visit to New York.

While MoveOn assails the mismanagement, casualties and high cost of the Iraq war, Freedom’s Watch presses the patriotism button and urges support for the troops, and even calls for a tougher policy against Iran, including a new war there if necessary.

An Associated Press report on Freedom’s Watch says that its organizers don’t see themselves as a single-issue movement like Swift Boat Veterans for Truth, which aimed to sink John Kerry’s presidential bid in 2004. It quotes the Freedom’s Watch president, Bradley Blakeman as planning “an organization that is a never-ending campaign.”

Mr. Blakeman was the director of scheduling and appointments at the Bush White House. Several other insiders and donors of the new organization have close ties with the administration and with Vice President Dick Cheney. Among them are Mary Matalin, Mr. Cheney’s former counselor and present adviser; Ari Fleischer, the former Bush White House spokesman; Mel Sembler who chaired the legal defense fund for I. Lewis “Scooter” Libby, Mr. Cheney’s former chief of staff, and Kevin E. Moley, a senior aide to Mr. Cheney in the 2000 presidential campaign.

What’s a Maine voter to do in the din of competing propaganda?

A healthy response is to listen to it all, keeping in mind that Maine’s two moderate Republican senators, Olympia Snowe and Susan Collins, are key figures in a deeply divided Senate. They should also maintain a good bit of skepticism, seek additional information from other sources.