Republican presidential candidate Mitt Romney named Wisconsin congressman Paul Ryan to be his running mate Saturday, choosing a politician who is viewed as a bridge between the Republican establishment and the small-tax, anti-big government tea party movement.

Ryan's conservative credentials are highly regarded by fellow Republican House members, while many polls during the primaries of
winter and spring found that Romney's own were suspect among the party's core, tea-party supporters.

With his choice, Romney sought to boost his own credentials, repair an image damaged by negative Democratic advertising and shift
the trajectory of a campaign that's seen him lose ground to President Barack Obama.