Vice-Presidential debates usually don't matter much.
But the face-off Thursday night could be an exception.
Democrats need Joe Biden to slow the momentum of Mitt Romney, who gained ground after a strong debate performance last week.
Republicans need Paul Ryan to build on that momentum.
Opinion polls show the race virtually tied with less than a month to go until the election.
We looked for five things to watch for in the debate.
First, expect more fireworks than we saw in the Presidential Debate.
Both Biden and Ryan seem comfortable playing the Vice-Presidential role of attack dog.
Biden is a seasoned debater.
He's been in the Senate for 36 years, which is almost as long as Ryan's been alive.
Biden's lack of a filter has gotten him into trouble at times in the past.
So he needs his mouth to work for him instead of against him Thursday night.
The 42-year old Ryan is one of the Conservative Movements foremost thinkers.
He's never debated at this level before, but he's been able to convince voters in his politically balanced district in Wisconsin, to send him back to Congress with easy wins over the last 14-years.
There's also fact versus fiction.
Biden has said he won't let any questionable claims go unchallenged and that he won't let Ryan gloss over policy details.
If either man thinks the other is lying, look for them to call him on it.
Another point to watch is Medicare.
Ryan has built his reputation on a proposal that would partially privatize the Government-run medical plan for seniors and handicapped to keep health care costs from crippling the federal budget.
Expect Biden to come out swinging on this one.
He'll argue that the plan would force retirees to pay thousands more for medical treatment.
But keep in mind, Ryan is a master at selling this plan to skeptical audiences.
There's also foreign policy.
Biden is the Former Chairman of the Senate Foreign Relations Committee.
He handled the Obama Administration's withdrawal from Iraq.
That sounds like advantage, Biden.
But, Ryan knowing foreign policy is perceived as a weakness for him, will be well briefed on foreign affairs.
He'll need to sound as if he knows enough to be credible.
Finally, looking to the future.
Remember, whoever is Vice-President, is a heartbeat away from the Presidency.
Both men know they have to look and sound Presidential, not just for Thursday night, but for the future.
They both could be running for President four years from now.
They don't want that road filled with potholes from gaffes at this debate.