Republican Newt Gingrich says he isn't leaving the party's presidential race and is vowing to continue all the way to the nominating convention.

Gingrich said Tuesday he is committed to carrying the banner of bold conservative colors all the way to Tampa to ensure, in his words, "the Republican Party never abandons the timeless conservative principles."

With only two primary victories and rival Mitt Romney on pace to win the nomination in June _ if not before _ Gingrich faces an uphill fight. He lost all three of Tuesday's primaries, contests in Wisconsin, Maryland and the District of Columbia.

The former House speaker says Republicans cannot win with what he calls "an Etch A Sketch platform that shows no principle or backbone," a criticism of Romney's shifts on policy issues.