08/06/2009 05:12 am ET Updated May 25, 2011

The Biggest Threat To Obama's Agenda: Democratic Centrists

Half a dozen members of the Senate Democratic Conference pose the biggest threat to President Obama's agenda, giving Senate Republicans a fighting chance to block the administration's major expansions of government.

GOP leaders have begun reaching out to these centrists, hoping they will buck their party on Obama's two biggest initiatives: healthcare reform and climate change legislation.

Read more on The Hill