How long till the Democratic National Convention? Because Hillary Clinton and Barack Obama went negative with new ads yesterday.

First, the Clinton camp offered up an ad explaining how Clinton's plan for a gas tax suspension (one that Obama does not support) will really help regular Americans, complete with regular Americans lamenting the price of gas.

Then Obama's campaign released an ad that talks about Clinton's negative campaigning, points to a NY Times editorial slamming her negative approach (it's her "hometown" newspaper, for Pete's sake!), and how the "same old Washington politics won’t fix our problems."

Two hundred eighteen delegates are at stake in tonight's primaries. According to the NY Times, Obama has 1,735 delegates while Clinton has 1,602 (the AP counts 1,742 for Obama and 1,607 for Clinton). And Politico has a list of five things to look for in Indiana and North Carolina.