CHARLOTTE, N.C. (AP) — U.S. Sen. Rand Paul is endorsing obstetrician Greg Brannon on the eve of the U.S. Senate primary election in North Carolina.

At a rally in Charlotte, the Kentucky senator said Monday that Brannon was the best candidate in Tuesday’s crowded GOP field.

Paul urged the crowd of 250 people to send another true conservative to the Senate.

He called Brannon a dragon slayer, someone who would shake up the status quo in Washington.

Earlier in the day, Mitt Romney, the 2012 Republican presidential nominee, announced his support for state House speaker Thom Tillis in the primary.

Romney says in an email message that Tillis is a conservative who solved problems while in Raleigh and he thinks Tillis will do the same in Washington.

Eight Republicans are seeking the party’s nomination.

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