Ron Johnson heading to Iowa

The Tea Party-backed senator quickly sought a national profile following his 2010 win, and narrowly lost a run for a GOP leadership position at the end of 2011. But his profile has been eclipsed in the Senate by other Tea Party-affiliated stars, including Sens. Marco Rubio (R-Fla.), Ted Cruz (R-Texas), Rand Paul (R-Ky.) and Mike Lee (R-Utah).

Iowa visits often indicate interest in a presidential run, though it's unclear what Johnson's goal might be for the trip. Two other Wisconsin Republicans, Gov. Scott Walker and Rep. Paul Ryan, are also viewed as potential presidential aspirants.

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