Senator John Warner is making a foray into presidential politics this weekend, campaigning in South Carolina for Republican John McCain.
Warner, who's retiring this year after five terms from Virginia, and Arizona Senator John Kyl will join McCain for two stops Sunday and two more Monday.
South Carolina's January 26 Republican primary is important for McCain, the Arizona senator who won last week's New Hampshire primary.
The 80-year-old Warner had scaled back his public appearances after he was hospitalized three times in October, the first for an irregular heartbeat.
Warner and McCain are Navy veterans.