Updated

Hillary Clinton and her Democratic rivals are set to square off Thursday night for the first time since the debate in Philadelphia two weeks ago left her feeling under attack — but don't expect anybody to make up and be friends.

Her top rivals, including Illinois Sen. Barack Obama and former North Carolina Sen. John Edwards, will likely be looking for another opening to expose her vulnerability when it comes to issues like trust and pandering, which recent polls show are concerns with her among voters.

The Las Vegas presidential debate is set for 8 p.m. EST on CNN.

Edwards already took a shot at the frontrunner Thursday, launching a new Web site called "Plants for Hillary," which is a clear reference to reports that her campaign planted favorable questions for audience members to ask.

The blows against Clinton are all part of the battle between Obama and Edwards to catch up to her in the polls. They took aim at her in Philadelphia, raising questions about her candor and willingness to answer tough questions, and leading her to declare her foes were "piling on because I'm winning."

This time around, Clinton will likely arrive ready with some jokes and self-deprecating humor to humanize herself, but she will also drive home the issue of leadership and experience.

Clinton strategist Mark Penn highlighted this in a memo Thursday, writing: "While opponents are strategizing and re-launching their campaigns with aggressive personal attacks on Sen. Clinton, one truth remains – running for president is not a qualification for president ... The voters are looking for someone who has the strength and experience to lead, and little has changed in the last few weeks outside of the massive media coverage of the attacks."

Clinton left the last debate fending off charges that she was hedging over her position on rights for undocumented residents, after she gave a confusing answer regarding her position on a now-failed New York plan to give illegal immigrants driver's licenses. Gov. Eliot Spitzer announced he was abandoning the effort Wednesday.

But Clinton may have only complicated matters in the run-up to the debate, when she said Wednesday she is now against granting driver's licenses to illegal immigrants. This was after her campaign first said she supported such efforts, and after Clinton later clarified the need for such programs depends on the state.

Her evolving and shifting stances gave her rivals more fodder in the hours before the Las Vegas showdown.

Edwards campaign said they were dizzied by the double talk.

Obama spokesman Bill Burton blasted Clinton for taking "two weeks and six different positions to answer one question on immigration."

Colleen Flanagan, a spokesman for candidate Chris Dodd, called Clinton's position "flip-flopping cubed. She was for it before she was against it, before she was for it, before she was against it."

But despite the attacks and reports about question-planting, the New York senator continues to maintain a comfortable lead in the polls, which have also given her high marks for experience.

A FOX News poll released Thursday showed Clinton with 44 percent support. The poll, conducted of 900 registered voters from Nov. 13-14, showed Obama with 23 percent and Edwards with 12 percent.

In early-voting Iowa, that lead is less of a sure thing. A CBS/New York Times poll of 1,273 likely Iowa voters conducted Nov. 2-11 showed the frontrunners in both parties feeling heat from their competitors. In the Democratic race, Obama and Edwards were shown in a near tie — with 22 and 23 percent respectively — and catching up to Clinton, who polled at 25 percent.

But in Nevada, which holds its Democratic caucuses Jan. 19, Clinton is in friendly territory.

A CNN poll of 389 likely Nevada voters taken from Nov. 9-13 showed Clinton with a whopping 51 percent, followed by Obama with 23 percent and Edwards with 11 percent.

While Obama won't resort to the intense criticism Clinton will likely face from Edwards, he could play on the experience question as it relates to the driver's license issue.

But even Edwards advisers concede he can't sound too shrill, as that would contrast visibly with his sunny, Southern moderate narrative in 2004.

Other scheduled participants in Thursday night's debate are New Mexico Gov. Bill Richardson, Sens. Joe Biden of Delaware and Chris Dodd of Connecticut and Ohio Rep. Dennis Kucinich.

The location of the debate highlights Nevada's new role in the presidential nominating process. Democrats allowed the state to move its caucus this year to Jan. 19, right after the traditional early state powerhouses Iowa and New Hampshire, in order to give an ethnically diverse Western state a bigger role in selecting the party's nominee. Democrats in Nevada hoped the early contest would force the candidates to pay closer heed to Western issues like water, grazing and mining rights.

National Democratic leaders believe the mountain West is a key area for the party, with fast-growing and once heavily Republican states like Nevada, Colorado and Arizona trending more Democratic in recent elections. The 2008 Democratic National Convention will be in Denver next August.

FOX News' Carl Cameron and Major Garrett and The Associated Press contributed to this report.