For months on the campaign trail, John Kerry (search) has criticized President Bush for running advertisements assailing the Democrat's record. Now, Kerry is the one on the attack.

Since last week's Republican convention, the Democratic presidential nominee has rolled out nine television ads bashing Bush on everything from factory jobs and family incomes to health insurance and coal technology.

Several commercials accuse Bush of "broken promises." Another spot suggests the president is aligned with "special interests." And, then there's one ad that lists job-loss statistics and says, "President Bush insists the economy is just fine."

In conjunction with a speech on the Iraq war, Kerry was unveiling a tenth Wednesday that accuses Bush of squandering $200 billion on Iraq while the United States suffers with "lost jobs" and "rising health care costs." The commercial claims: "George Bush's wrong choices have weakened us here at home."

The post-Labor Day move comes at a time when undecided voters typically start paying more attention to the race. They make up a small group that both sides are courting feverishly in a presidential race that's expected to be very close come Nov. 2.

"The conversation is shifting right now into the choice between the two candidates," said Jenny Backus, a consultant who has worked with the Democratic National Committee. "Kerry's campaign told everybody who Kerry is, and now they're defining Bush and trying to present Kerry as an acceptable alternative to him."

The change also comes as polls show the president getting a bounce in support from his convention and as Democrats pressure Kerry to turn up the heat on the GOP incumbent following a month during which ads by an outside group accusing Kerry of exaggerating his Vietnam service took their toll.

This month in ads, Kerry is trying to get off the defensive on national security, where Bush has an advantage, and instead focus on domestic issues such as jobs, health care and education that historically have been the strongest areas for Democrats.

To succeed, Kerry must make sharper distinctions between himself and Bush to persuade voters to reject the status quo — and a Republican with four years at the helm — in favor of a ticket that has never been in the White House but promises, as Kerry's running mate John Edwards often says, "tomorrow can be better than today."

So, one ad, with the tag line "the wrong direction for America," shows Bush during his convention speech promoting his Medicare prescription drug benefit and claiming "now seniors are getting immediate help."

"The very next day George Bush imposes the biggest Medicare premium increase in history while prescription drug costs still skyrocket," the ad says, adding that Kerry has "a plan to lower the cost of health care and take America in a new direction."

In a tactic used by Bush's campaign and Democratic-leaning outside groups, Kerry's campaign also followed Bush over the weekend, running six TV ads on state-specific issued in six media markets — Cleveland; Milwaukee; Cedar Rapids, Iowa; Erie, Pa.; Scranton, Pa., and Parkersburg, W.Va. — to coincide with the president's post-convention visits to those areas.

"Four years ago, George Bush came to West Virginia promising $2 billion for clean coal technology. Four years later, Bush has broken his promise to invest in coal and cut $15 million from mine safety," an ominous-sounding announcer says. "Now, Bush is back. But around here, we remember Bush's broken promises."

Another commercial running in several states lays out Kerry's overall argument: "The fundamental choice in this election is between a president who will fight for the middle class, and a president who sides with special interests in this country."

Most of Kerry's previous ads since he wrapped up the Democratic nomination in early March drew subtle differences between his proposals and Bush's policies, and focused mainly on introducing Kerry and his agenda. Only a few of those mentioned the president.

Bush, however, spent a large chunk of his $120 million pre-convention ad money on commercials looking at the Democrat's 19-year Senate voting record and painting him as a waffler on taxes and terrorism.

As Kerry traveled the country in spring and summer, he often claimed he had not run one negative ad and complained about Bush's onslaught. However, during the Democratic primary season, Kerry ran ads criticizing Bush. And, while Kerry mostly stayed sunny on the air before Labor Day, his supporters ran some $80 million worth of anti-Bush ads.