Eight influential senators play key roles in health care debate

As the Senate begins debate this week on a 10 year, $848 billion health care bill, a few lawmakers are positioned to exert enormous influence over President Obama's top priority as the legislation moves toward its final stages.

They include members of both parties, newcomers to Capitol Hill and old hands. Some worry about the government's reach into health care; others are concerned the proposal doesn't go far enough.

All will be critical as Obama hunts for the 60 votes he will need to pass a health care bill before the end of the year.

"We've got a long way to go between here and there," said Norm Ornstein, a congressional scholar with the American Enterprise Institute. "There's a lot of serious negotiations that will go on in the background to try to figure out the sweet spot here."

Three weeks after the House narrowly passed its version of the legislation, the Senate must now wrestle with how to expand health coverage to millions of Americans, how to pay for it, whether to include a government-run insurance program and how to deal with the complex abortion issue.

Virtually all Republicans are opposed, so Democratic leaders such as Senate Majority Leader Harry Reid, D-Nev., must focus on the demands of a small group of moderate Democrats without alienating more liberal members of the caucus.

Here are some of the senators who are shaping up to be among the most influential.