Ryan told Fox he is convinced that Romney "has the skills, the tenacity and the courage" to lead the party in the race against President Obama this fall.
He also said that "if we drag this thing on through summer, it's going to be harder" to turn Obama out of office.
The key endorsement from Ryan, a Wisconsin Republican, comes on a day when Romney gives a speech on the economy in Appleton, Wis. Wisconsin's presidential primary is Tuesday. Romney leads Rick Santorum in the Badger State by 7 percentage points, according to an NBC News/Marist poll out Friday morning.
Ryan's budget plan is destined for almost sure defeat in the Democrat-led Senate, but its passage in the House will be used by Republicans to contrast the spending priorities of Democrats and Republicans.
Ryan seemed to leave the door open for a possible vice president slot during an appearance last weekend on "Fox News Sunday" when he said, "I would have to consider it, but it's not something I'm even thinking about… it's not a bridge I've even come close to crossing."
Wisconsin will be the focal point throughout the weekend of the race for the GOP presidential nomination. Romney, Santorum and Newt Gingrich will be there Friday, and all three will be there again on Saturday. The main event on Saturday: Speeches at the Wisconsin Faith & Freedom Coalition Presidential Kick-Off event in Waukesha.
You have to wonder if Romney and Gingrich will have another secret meeting while they are both in Wisconsin. Romney confirmed Thursday that they met in New Orleans before the Louisiana primary.
And then there is this: Get out the birthday candles. Al Gore, former vice president and almost president, turns 64 on Saturday.
Updated at 9:21 a.m. EDT
Sources: Yahoo! News, Yahoo! News Reporter Olivier Knox, ABC News, Fox News, Associated Press.
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