The acknowledgment by U.N. officials of significant fraud in Afghanistan's presidential election comes as the United States debates the future of America's eight-year military involvement in the country. U.S. legislators are expressing sharp differences on the best way forward in Afghanistan while the Obama administration conducts a review of U.S. strategy in the war-torn nation.

American lawmakers from both major political parties agree on one central idea: that Afghanistan must not revert to a safe haven for terrorists and militant extremists. Beyond that, consensus is hard to find.

Senate Judiciary Committee member Sen. Dianne Feinstein, D-Calif. speaks on Capitol Hill in Washington
Democratic Senator Dianne Feinstein of California says President Barack Obama should heed the recommendation of his top general in Afghanistan, Stanley McChrystal, and significantly boost U.S. troop presence in the country.

"You have got to stabilize this country. You leave this country, and the Taliban are increasing all of the time, they are taking over more," she said. "It will have a dramatic impact on Pakistan one day - I really believe that. I do not know how you put somebody in who is as crackerjack as General McChrystal, who gives the president very solid recommendations, and not take those recommendations."

Feinstein was speaking on ABC's This Week program.

But a fellow-Democrat and the chairman of the Senate Armed Services Committee, Carl Levin of Michigan, says rather than sending more troops to Afghanistan, the United States should focus on training Afghan security forces. Appearing on NBC's Meet the Press program, Levin noted McChrystal's report, which has been leaked to the news media, deals with more than just troops levels.

Senate Armed Services Committee Chairman Sen. Carl Levin of Michigan speaks during a news conference on Afghanistan"General McChrystal said a number of things, not just that he needs more resources, whatever that number is," said Levin. "He also says we need a new strategy, and that that is even more important than the resources. I am saying, at this time do not send more combat troops . But I say focus on the Afghan forces, the army, faster, larger, better equipped."

The White House says a final decision by President Obama on continued U.S. military engagement in Afghanistan is weeks away.

Widespread reports of Afghan government corruption and election fraud are disheartening to U.S. policymakers, since America's efforts in Afghanistan are in support of the government in Kabul, with the hope that Afghanistan will one day assume full responsibility for its security.

Whatever the Afghan government's shortcomings, Republican Senator Saxby Chambliss says the United States cannot afford to allow the situation in Afghanistan to deteriorate.

"We have got to quell the violence. We have to slow down the Taliban," said Chambliss. "That means prevailing militarily, and obviously that is where the additional resources in the form of troops come in."

Chambliss was speaking on ABC's This Week.