McCain in Florida, Obama in Indiana

John McCain continued to hammer Democratic rival Barack Obama on taxes and national security today, campaigning in must-win Florida.

Giving what has become his stock stump speech, McCain asserted that Obama is more concerned about using taxes to "spread the wealth" than creating more wealth and more jobs. McCain is on a "Joe the plumber" bus tour across the Sunshine State, targeting blue-collar workers and small business owners.

Obama campaign spokesman Tommy Vietor responded to McCain's remarks on taxes, “Last week Senator McCain called Obama’s tax cuts for working people ‘welfare.’ Today he’s claiming Senator Obama doesn’t do enough to help the unemployed. The only thing consistent about these attacks is how dishonest they are. All of Senator Obama’s tax credits only go to workers and they always have. The McCain campaign is once again trying to distort our plan to distract from the fact that Senator Obama’s tax plan will help the middle class while Senator McCain leaves out 100 million Americans.”

McCain was also incredulous of Obama's explanation for running mate Joe Biden predicting that enemies would test Obama early in his presidency -- that Biden engages in "rhetorical flourishes."

"Really? Really?" McCain said, chuckling. "That's another way of saying he accidentally delivered some straight talk to America."

"I have been tested, Senator Obama has not been tested. And it shows," McCain added.

Obama, meanwhile, is in Indianapolis for his last rally before leaving the campaign trail to see his ill grandmother. In advance of the event, his campaign released a radio ad from that Indiana native and small-town troubadour, John Mellencamp.

"I’ve seen a lot of small towns, but now I’m seeing small towns across America dying," the rock star says. "Folks losing their jobs and their homes… eight years of George Bush have really hurt. And - John McCain is just more of the same. Over the last eight years, thousands of Hoosier workers have seen their jobs sent out of this country. John McCain will keep giving tax breaks to companies shipping American jobs overseas…

"Barack Obama gets it, he sees the value in American made products and a strong American labor force; He’ll end tax breaks for companies shipping our jobs overseas and give a hard working family a break. This is John Mellencamp, and I’m proud to support Barack Obama, because whether you live in a small town or a big city, it’s time for a change."

Meanwhile, the latest Big Ten Battleground Poll shows Obama with significant leads in Indiana and seven other Midwestern states.

McCain led narrowly in Indiana last month, but now Obama leads 51 percent to 41 percent.

The two were tied in Ohio and Pennsylvania, but now Obama leads in Ohio 53 percent to 41 percent and in Pennsylvania 52 percent to 41 percent.