All eyes turn to Sinema as Democrats face a week that could transform Biden's presidency

Democrats this week have the chance to validate their monopoly on political power in Washington, create a legacy of true significance for President Joe Biden and even boost their hopes in daunting midterm elections in three months.

But first they must push a back-from-the-dead climate and health care initiative through the Senate using their tiny majority, notably by locking in the crucial vote of moderate Arizona Sen. Kyrsten Sinema, who has yet to sign off on a bill that may not save Democrats in November but may at least give them a big new win to run on.

Tensions are, meanwhile, soaring between the parties, especially over a Republican blockade of a bill that would fund health care for veterans sickened by exposure to burn pits during service in America's foreign wars. The move opened up the GOP to accusations of cruelty -- and, for once, Republican leader Mitch McConnell has looked outmaneuvered.