(CNN) - Barack Obama is out with two more television ads directly attacking rival John McCain - the latest in a string of negative commercials the Illinois senator's campaign has launched over the past week as polls show the race for the White House has essentially become a dead heat.
The first ad - hitting airwaves in the crucial battleground state of Nevada - attacks the Arizona senator over his support of storing nuclear waste in the state's Yucca mountain. "Dangerous" is the second Obama campaign spot in the state to criticize McCain on that hot-button issue for many Nevadans.
"John McCain says he's opposed to nuclear waste going through Arizona, but he wants to dump it here in Nevada. If you don't want nuclear waste here, you don't want John McCain here," the ad's narrator says, as a picture of the White House flashes.
The second spot - called "Better Off" - is similar to an ad the campaign already has in the mix, featuring John McCain's comment at a January primary debate stating, "we've had a pretty good prosperous time." It then shows several citizens from Ohio and Indiana discussing their own economic woes as a screen graphic asks, "How can John McCain fix the economy when he doesn't think it's broken?"