Sen. Lindsey Graham has not officially endorsed any of the GOP presidential nominees, but today the South Carolina Republican seemed to be rooting for Mitt Romney.

Speaking on CNN’s “State of the Union,” he said that the drawn-out, bruising presidential primary contest has actually made Romney more likely to win the nomination.

“Gov. Romney is a better candidate because of the primary process,” Graham said. “By the time Florida came around Romney took it to the field, and the upside of the process is that our frontrunner has gotten stronger.”

Sen. John McCain (R-Ariz.), who is backing Romney, told CNN he was confident that Romney would win Tuesday’s primaries, in Michigan and McCain’s home state of Arizona, and that Super Tuesday would all but seal the nomination.

Arizona Gov. Jan Brewer, appearing on NBC’s “Meet the Press,” also endorsed Romney, joining a long list of elected officials who are backing the former Massachusetts governor, including Michigan Gov. Rick Snyder and 79 Members of Congress.

The most recent polls show former Sen. Rick Santorum (R-Pa.) and Romney neck and neck, a sign that the Republican electorate is not as committed as its representatives in Washington. Still, McCain said he did not expect a brokered convention this summer or any late-entering candidates.